{"id":2676,"date":"2026-07-16T02:42:03","date_gmt":"2026-07-16T02:42:03","guid":{"rendered":"https:\/\/www.sapphire-windows.com\/?p=2676"},"modified":"2026-07-16T02:42:15","modified_gmt":"2026-07-16T02:42:15","slug":"common-inspection-methods-for-sapphire-windows-before-shipment","status":"publish","type":"post","link":"https:\/\/www.sapphire-windows.com\/th\/common-inspection-methods-for-sapphire-windows-before-shipment\/","title":{"rendered":"Common Inspection Methods for Sapphire Windows Before Shipment"},"content":{"rendered":"<p class=\"wp-block-paragraph\"><a href=\"https:\/\/www.sapphire-windows.com\/th\/product-category\/%e0%b8%ab%e0%b8%99%e0%b9%89%e0%b8%b2%e0%b8%95%e0%b9%88%e0%b8%b2%e0%b8%87%e0%b9%81%e0%b8%8b%e0%b8%9f%e0%b9%84%e0%b8%9f%e0%b8%a3%e0%b9%8c\/\">\u0e2b\u0e19\u0e49\u0e32\u0e15\u0e48\u0e32\u0e07\u0e41\u0e0b\u0e1f\u0e44\u0e1f\u0e23\u0e4c<\/a> are used in optical instruments, semiconductor equipment, laser systems, pressure vessels, aerospace sensors and other applications where both optical transparency and mechanical durability are required.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Before shipment, a sapphire window must be inspected to verify that its dimensions, surface condition, optical performance and packaging comply with the customer\u2019s drawing and purchase specification.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This inspection is more complex than simply checking whether the window is transparent or free from visible cracks. A sapphire window can appear acceptable to the naked eye while still having excessive thickness variation, surface-form error, wedge, coating non-uniformity or microscopic contamination.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A complete quality-control process may include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Material and crystal-orientation verification<\/li>\n\n\n\n<li>Visual inspection<\/li>\n\n\n\n<li>Dimensional measurement<\/li>\n\n\n\n<li>Thickness and total thickness variation measurement<\/li>\n\n\n\n<li>Surface-quality inspection<\/li>\n\n\n\n<li>Flatness and transmitted wavefront testing<\/li>\n\n\n\n<li>Parallelism or wedge inspection<\/li>\n\n\n\n<li>Surface-roughness measurement<\/li>\n\n\n\n<li>Optical transmission testing<\/li>\n\n\n\n<li>Coating inspection<\/li>\n\n\n\n<li>Edge and chamfer inspection<\/li>\n\n\n\n<li>Cleanliness verification<\/li>\n\n\n\n<li>Final documentation and packaging inspection<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The exact inspection plan depends on the function of the sapphire window and the tolerances specified by the customer.<\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-large\"><img fetchpriority=\"high\" decoding=\"async\" width=\"1024\" height=\"683\" src=\"https:\/\/www.sapphire-windows.com\/wp-content\/uploads\/2026\/07\/Common-Inspection-Methods-for-Sapphire-Windows-Before-Shipment-1024x683.png\" alt=\"\" class=\"wp-image-2677\" srcset=\"https:\/\/www.sapphire-windows.com\/wp-content\/uploads\/2026\/07\/Common-Inspection-Methods-for-Sapphire-Windows-Before-Shipment-1024x683.png 1024w, https:\/\/www.sapphire-windows.com\/wp-content\/uploads\/2026\/07\/Common-Inspection-Methods-for-Sapphire-Windows-Before-Shipment-300x200.png 300w, https:\/\/www.sapphire-windows.com\/wp-content\/uploads\/2026\/07\/Common-Inspection-Methods-for-Sapphire-Windows-Before-Shipment-768x512.png 768w, https:\/\/www.sapphire-windows.com\/wp-content\/uploads\/2026\/07\/Common-Inspection-Methods-for-Sapphire-Windows-Before-Shipment-18x12.png 18w, https:\/\/www.sapphire-windows.com\/wp-content\/uploads\/2026\/07\/Common-Inspection-Methods-for-Sapphire-Windows-Before-Shipment-600x400.png 600w, https:\/\/www.sapphire-windows.com\/wp-content\/uploads\/2026\/07\/Common-Inspection-Methods-for-Sapphire-Windows-Before-Shipment.png 1536w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">1. Why Pre-Shipment Inspection Is Important<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Sapphire is known for its high hardness, chemical resistance, thermal stability and mechanical strength. However, these material advantages do not automatically guarantee that a finished window will perform correctly in an optical system.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Manufacturing processes such as crystal cutting, grinding, lapping, polishing, cleaning and coating can introduce dimensional or optical deviations.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Typical risks include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Incorrect diameter or outline dimensions<\/li>\n\n\n\n<li>Excessive thickness variation<\/li>\n\n\n\n<li>Surface scratches or pits<\/li>\n\n\n\n<li>\u0e0a\u0e34\u0e1b Edge<\/li>\n\n\n\n<li>Poor surface flatness<\/li>\n\n\n\n<li>Excessive wedge<\/li>\n\n\n\n<li>High surface roughness<\/li>\n\n\n\n<li>Internal inclusions<\/li>\n\n\n\n<li>\u0e02\u0e49\u0e2d\u0e1a\u0e01\u0e1e\u0e23\u0e48\u0e2d\u0e07\u0e02\u0e2d\u0e07\u0e0a\u0e31\u0e49\u0e19\u0e40\u0e04\u0e25\u0e37\u0e2d\u0e1a<\/li>\n\n\n\n<li>Particle contamination<\/li>\n\n\n\n<li>Packaging damage<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Pre-shipment inspection is intended to identify these issues before the product reaches the customer.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For standard industrial windows, inspection may rely on visual examination and basic dimensional measurements. For laser-grade or interferometric components, the process may require calibrated interferometers, spectrophotometers, surface profilers and detailed inspection reports.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">2. Review of Drawings and Specifications<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Inspection should begin with a review of the customer\u2019s drawing, purchase order and technical requirements.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The inspector should confirm:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Material grade<\/li>\n\n\n\n<li>Sapphire orientation<\/li>\n\n\n\n<li>\u0e23\u0e39\u0e1b\u0e17\u0e23\u0e07\u0e02\u0e2d\u0e07\u0e2b\u0e19\u0e49\u0e32\u0e15\u0e48\u0e32\u0e07<\/li>\n\n\n\n<li>Diameter, length and width<\/li>\n\n\n\n<li>Thickness and thickness tolerance<\/li>\n\n\n\n<li>\u0e23\u0e39\u0e23\u0e31\u0e1a\u0e41\u0e2a\u0e07<\/li>\n\n\n\n<li>Surface-quality requirement<\/li>\n\n\n\n<li>Flatness requirement<\/li>\n\n\n\n<li>Parallelism or wedge requirement<\/li>\n\n\n\n<li>Surface roughness<\/li>\n\n\n\n<li>Edge treatment<\/li>\n\n\n\n<li>Optical coating<\/li>\n\n\n\n<li>Transmission wavelength<\/li>\n\n\n\n<li>Inspection standard<\/li>\n\n\n\n<li>Required reports or certificates<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">This step is important because some specifications can be interpreted differently unless the measurement method is clearly defined.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For example, a drawing may specify \u03bb\/4 flatness without stating the test wavelength, clear aperture or whether the value refers to surface deviation or wavefront error.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Similarly, a scratch-dig value should identify the applicable inspection system. ISO 10110-7 specifies how acceptable surface imperfections are indicated within a defined test region, including localized imperfections, long scratches and edge chips.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Inspection results should always be evaluated against the agreed drawing rather than against a general idea of what constitutes a \u201cgood\u201d sapphire window.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">3. Visual Surface Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Visual inspection is normally one of the first quality-control steps.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The sapphire window is examined under controlled lighting to identify visible defects such as:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Scratches<\/li>\n\n\n\n<li>Digs<\/li>\n\n\n\n<li>\u0e2b\u0e25\u0e38\u0e21<\/li>\n\n\n\n<li>\u0e23\u0e2d\u0e22\u0e41\u0e15\u0e01<\/li>\n\n\n\n<li>Chips<\/li>\n\n\n\n<li>Polishing marks<\/li>\n\n\n\n<li>Stains<\/li>\n\n\n\n<li>Residue<\/li>\n\n\n\n<li>\u0e25\u0e32\u0e22\u0e19\u0e34\u0e49\u0e27\u0e21\u0e37\u0e2d<\/li>\n\n\n\n<li>Coating blemishes<\/li>\n\n\n\n<li>Foreign particles<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Inspection conditions may include a dark background, directional illumination, magnification and a defined viewing distance.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The inspector should evaluate the entire optical aperture, while also checking whether any defects are located inside or outside the functional clear aperture.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A small defect near the outer edge may not affect the optical path, while the same defect in the center of the clear aperture may be unacceptable.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Visual inspection should also distinguish between surface contamination and permanent damage. A mark caused by cleaning residue may disappear after recleaning, whereas a polishing scratch remains part of the surface.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">4. Scratch-Dig Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Scratch-dig inspection evaluates localized surface imperfections.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In common optical notation, a specification such as 60-40 or 20-10 indicates the permitted scratch and dig quality level. Lower values generally represent stricter surface-quality requirements.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Typical application levels may include:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th>Scratch-Dig Level<\/th><th>General Application<\/th><\/tr><tr><td>80-50<\/td><td>Commercial protective windows<\/td><\/tr><tr><td>60-40<\/td><td>General industrial optics<\/td><\/tr><tr><td>40-20<\/td><td>Precision imaging systems<\/td><\/tr><tr><td>20-10<\/td><td>Laser and scientific optics<\/td><\/tr><tr><td>10-5<\/td><td>High-precision optical systems<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Scratch-dig inspection should not be confused with surface-roughness measurement.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Scratch-dig evaluates isolated visible imperfections, while roughness evaluates microscopic texture over a measured area.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">ISO 10110-7 addresses the indication of surface imperfections on optical drawings, while ISO 14997 describes practical methods for evaluating such imperfections.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For coated sapphire windows, inspection must also include coating scratches, pinholes, stains and localized adhesion defects.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">5. Dimensional Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Dimensional inspection verifies that the physical geometry of the sapphire window matches the drawing.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Common measurements include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Outside diameter<\/li>\n\n\n\n<li>Length and width<\/li>\n\n\n\n<li>Corner radius<\/li>\n\n\n\n<li>\u0e40\u0e2a\u0e49\u0e19\u0e1c\u0e48\u0e32\u0e19\u0e28\u0e39\u0e19\u0e22\u0e4c\u0e01\u0e25\u0e32\u0e07\u0e02\u0e2d\u0e07\u0e23\u0e39<\/li>\n\n\n\n<li>Slot dimensions<\/li>\n\n\n\n<li>Step dimensions<\/li>\n\n\n\n<li>Chamfer width<\/li>\n\n\n\n<li>Bevel angle<\/li>\n\n\n\n<li>\u0e04\u0e27\u0e32\u0e21\u0e2b\u0e19\u0e32<\/li>\n\n\n\n<li>Edge thickness<\/li>\n\n\n\n<li>Position of drilled or machined features<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Depending on the tolerance, inspectors may use:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Digital calipers<\/li>\n\n\n\n<li>Outside micrometers<\/li>\n\n\n\n<li>Height gauges<\/li>\n\n\n\n<li>Tool microscopes<\/li>\n\n\n\n<li>Optical comparators<\/li>\n\n\n\n<li>Coordinate measuring machines<\/li>\n\n\n\n<li>Non-contact vision measurement systems<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Contact measurement must be performed carefully. Although sapphire is highly resistant to scratching, localized force from a measuring tool can damage thin edges or coated surfaces.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For precision components, measurement equipment should be calibrated and suitable for the required uncertainty.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">6. Thickness Measurement<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Thickness is a critical parameter because it affects mechanical strength, optical path length, assembly fit and pressure resistance.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Thickness may be measured using:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Mechanical micrometers<\/li>\n\n\n\n<li>Digital thickness gauges<\/li>\n\n\n\n<li>Non-contact optical gauges<\/li>\n\n\n\n<li>Interferometric thickness systems<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Measurements should normally be taken at several positions rather than at only one point.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For a circular sapphire window, inspection points may include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Center<\/li>\n\n\n\n<li>Four or more points around the middle radius<\/li>\n\n\n\n<li>Locations near the usable edge<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">This measurement pattern helps identify whether the window has a uniform thickness or a wedge-shaped profile.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The measuring force must be controlled, particularly for thin windows. Excessive force can bend the part and produce an inaccurate reading.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">7. Total Thickness Variation<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Total thickness variation, commonly abbreviated as TTV, is the difference between the maximum and minimum measured thickness across the specified area.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">TTV can be expressed as:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>TTV = Maximum Thickness \u2212 Minimum Thickness<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Low TTV is important in applications such as:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Optical imaging<\/li>\n\n\n\n<li>\u0e2d\u0e38\u0e1b\u0e01\u0e23\u0e13\u0e4c\u0e40\u0e0b\u0e21\u0e34\u0e04\u0e2d\u0e19\u0e14\u0e31\u0e01\u0e40\u0e15\u0e2d\u0e23\u0e4c<\/li>\n\n\n\n<li>Precision sensor assemblies<\/li>\n\n\n\n<li>Bonded optical stacks<\/li>\n\n\n\n<li>Interferometric systems<\/li>\n\n\n\n<li>Windows requiring strict parallelism<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A sapphire window can meet its nominal thickness tolerance but still fail the TTV requirement.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For example, every measurement may fall within the permitted overall thickness range, but the difference between one side and the other may still be too large.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">TTV may be measured using mechanical mapping systems, capacitive gauges or optical interferometric methods, depending on the required precision.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">8. Diameter, Shape and Outline Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">For round windows, the inspector should verify:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Nominal diameter<\/li>\n\n\n\n<li>Diameter tolerance<\/li>\n\n\n\n<li>Roundness<\/li>\n\n\n\n<li>Edge condition<\/li>\n\n\n\n<li>Chamfer consistency<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">For rectangular or custom-shaped windows, additional inspection may include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Length and width<\/li>\n\n\n\n<li>Squareness<\/li>\n\n\n\n<li>Parallel side dimensions<\/li>\n\n\n\n<li>Corner radius<\/li>\n\n\n\n<li>Profile accuracy<\/li>\n\n\n\n<li>\u0e15\u0e33\u0e41\u0e2b\u0e19\u0e48\u0e07\u0e23\u0e39<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A window with correct nominal dimensions may still create assembly problems if it has poor roundness or an inaccurate corner profile.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Vision measurement systems are useful for irregular shapes because they can compare the measured outline with CAD data.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">9. Edge and Chamfer Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The edge of a sapphire window is mechanically important because cracks often begin at damaged edges.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Edge inspection should identify:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Chips<\/li>\n\n\n\n<li>\u0e23\u0e2d\u0e22\u0e41\u0e15\u0e01\u0e02\u0e19\u0e32\u0e14\u0e40\u0e25\u0e47\u0e01<\/li>\n\n\n\n<li>Sharp corners<\/li>\n\n\n\n<li>Uneven chamfers<\/li>\n\n\n\n<li>Grinding marks<\/li>\n\n\n\n<li>Localized fracture<\/li>\n\n\n\n<li>Incomplete edge polishing<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A chamfer or bevel helps remove the fragile sharp edge created during cutting and grinding.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The inspector may verify:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Chamfer width<\/li>\n\n\n\n<li>Chamfer angle<\/li>\n\n\n\n<li>Uniformity around the perimeter<\/li>\n\n\n\n<li>Maximum permitted edge-chip size<\/li>\n\n\n\n<li>Whether chips enter the clear aperture<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Edge defects that do not significantly affect optical transmission can still reduce mechanical strength. This is especially important for pressure windows, vacuum viewports and components installed in compression mounts.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">10. Surface Flatness Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Flatness describes how much an optical surface deviates from an ideal plane.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">It may be specified using physical units or fractions of a wavelength, such as:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>1\u03bb<\/li>\n\n\n\n<li>\u03bb\/2<\/li>\n\n\n\n<li>\u03bb\/4<\/li>\n\n\n\n<li>\u03bb\/10<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The applicable reference wavelength and measurement aperture should be stated.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">ISO 10110-5 specifies rules for indicating surface-form tolerances on optical drawings.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Flatness is commonly measured with an optical interferometer. The sapphire surface is compared with a calibrated reference surface, and the resulting interference pattern is analyzed.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Modern phase-shifting interferometers can generate a full surface map showing:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Peak-to-valley deviation<\/li>\n\n\n\n<li>RMS surface error<\/li>\n\n\n\n<li>Power<\/li>\n\n\n\n<li>Irregularity<\/li>\n\n\n\n<li>Astigmatism<\/li>\n\n\n\n<li>Local surface deformation<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">NIST describes direct interferometric comparison with a master flat and three-flat calibration methods for precision flatness measurement.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The support method is especially important when measuring large or thin sapphire windows. Gravity, edge clamping or fixture pressure can deform the part and alter the measured surface form. NIST research has shown that mounting-induced deformation and gravitational sag can materially influence precision flatness results.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">11. Parallelism and Wedge Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Parallelism describes the angular relationship between the front and rear optical surfaces.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If the two surfaces are not parallel, the window contains wedge.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Parallelism may be specified in:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Arcminutes<\/li>\n\n\n\n<li>Arcseconds<\/li>\n\n\n\n<li>Milliradians<\/li>\n\n\n\n<li>Microradians<\/li>\n\n\n\n<li>Thickness variation<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Excessive wedge can cause:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u0e01\u0e32\u0e23\u0e40\u0e1a\u0e35\u0e48\u0e22\u0e07\u0e40\u0e1a\u0e19\u0e02\u0e2d\u0e07\u0e25\u0e33\u0e41\u0e2a\u0e07<\/li>\n\n\n\n<li>Image displacement<\/li>\n\n\n\n<li>Double reflections<\/li>\n\n\n\n<li>Optical alignment error<\/li>\n\n\n\n<li>Unequal optical path length<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Inspection methods include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Multiple-point thickness measurement<\/li>\n\n\n\n<li>Autocollimator testing<\/li>\n\n\n\n<li>Interferometric measurement<\/li>\n\n\n\n<li>Laser beam-deviation testing<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">An autocollimator can observe reflections from the front and rear surfaces. The angular separation between the reflected images can then be used to determine the surface relationship.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For laser windows, a deliberate wedge may sometimes be specified to prevent unwanted interference between reflections. Therefore, the inspector should not assume that perfectly parallel surfaces are always required.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">12. Transmitted Wavefront Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Surface flatness measures the form of an individual surface, but transmitted wavefront testing evaluates the combined optical effect of the entire sapphire window.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Transmitted wavefront error may result from:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Front-surface deformation<\/li>\n\n\n\n<li>Rear-surface deformation<\/li>\n\n\n\n<li>Thickness variation<\/li>\n\n\n\n<li>Crystal inhomogeneity<\/li>\n\n\n\n<li>Wedge<\/li>\n\n\n\n<li>Residual stress<\/li>\n\n\n\n<li>Mounting deformation<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">During inspection, a reference beam passes through the sapphire window, and the transmitted wavefront is compared with a reference wavefront.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This test is particularly important for:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>High-resolution imaging<\/li>\n\n\n\n<li>\u0e01\u0e32\u0e23\u0e27\u0e31\u0e14\u0e14\u0e49\u0e27\u0e22\u0e27\u0e34\u0e18\u0e35\u0e2d\u0e34\u0e19\u0e40\u0e15\u0e2d\u0e23\u0e4c\u0e40\u0e1f\u0e2d\u0e42\u0e23\u0e40\u0e21\u0e15\u0e23\u0e35<\/li>\n\n\n\n<li>Laser beam delivery<\/li>\n\n\n\n<li>Optical metrology<\/li>\n\n\n\n<li>Precision sensing<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A sapphire window can have acceptable individual surface flatness but still produce unacceptable transmitted wavefront distortion.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Therefore, demanding applications may specify both surface flatness and transmitted wavefront error.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">13. Surface-Roughness Measurement<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Surface roughness describes microscopic variations remaining after polishing.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Common parameters include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Ra<\/li>\n\n\n\n<li>Rq<\/li>\n\n\n\n<li>RMS roughness<\/li>\n\n\n\n<li>Peak-to-valley height<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Measurement methods may include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Stylus profilometry<\/li>\n\n\n\n<li>Atomic force microscopy<\/li>\n\n\n\n<li>White-light interferometry<\/li>\n\n\n\n<li>Coherence-scanning interferometry<\/li>\n\n\n\n<li>Optical profilometry<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">NIST defines coherence-scanning interferometry as a surface-topography measurement method that localizes interference fringes during an optical-path scan.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Surface roughness affects:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Optical scattering<\/li>\n\n\n\n<li>Laser damage resistance<\/li>\n\n\n\n<li>Coating adhesion<\/li>\n\n\n\n<li>Short-wavelength transmission<\/li>\n\n\n\n<li>\u0e04\u0e27\u0e32\u0e21\u0e15\u0e48\u0e32\u0e07\u0e02\u0e2d\u0e07\u0e20\u0e32\u0e1e<\/li>\n\n\n\n<li>Cleaning behavior<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A surface that passes scratch-dig inspection may still have excessive microscopic roughness.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For ultraviolet, laser or low-scatter applications, roughness may require separate measurement even when the surface appears visually perfect.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">14. Optical Transmission Testing<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Transmission testing verifies how much light passes through the sapphire window across the required wavelength range.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A spectrophotometer is commonly used to measure transmission from ultraviolet through visible or infrared wavelengths, depending on the equipment configuration and sapphire grade.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The test can identify:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Reduced transmission<\/li>\n\n\n\n<li>Unexpected absorption<\/li>\n\n\n\n<li>Incorrect coating performance<\/li>\n\n\n\n<li>Material contamination<\/li>\n\n\n\n<li>Thickness-related optical loss<\/li>\n\n\n\n<li>Spectral non-uniformity<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Transmission should be measured according to the actual application band.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A visible-light measurement is not sufficient for a window intended for ultraviolet or infrared operation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For coated windows, the measured transmission represents the combined effect of:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Sapphire absorption<\/li>\n\n\n\n<li>\u0e01\u0e32\u0e23\u0e2a\u0e30\u0e17\u0e49\u0e2d\u0e19\u0e02\u0e2d\u0e07\u0e1c\u0e34\u0e27\u0e2b\u0e19\u0e49\u0e32<\/li>\n\n\n\n<li>\u0e1b\u0e23\u0e30\u0e2a\u0e34\u0e17\u0e18\u0e34\u0e20\u0e32\u0e1e\u0e01\u0e32\u0e23\u0e40\u0e04\u0e25\u0e37\u0e2d\u0e1a<\/li>\n\n\n\n<li>\u0e04\u0e27\u0e32\u0e21\u0e2b\u0e19\u0e32\u0e02\u0e2d\u0e07\u0e2b\u0e19\u0e49\u0e32\u0e15\u0e48\u0e32\u0e07<\/li>\n\n\n\n<li>\u0e17\u0e34\u0e28\u0e17\u0e32\u0e07\u0e02\u0e2d\u0e07\u0e1c\u0e25\u0e36\u0e01<\/li>\n\n\n\n<li>Incident angle<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">15. Anti-Reflection Coating Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Many sapphire windows are supplied with anti-reflection coatings to reduce reflection and improve transmission.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Coating inspection may include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Visual examination<\/li>\n\n\n\n<li>Spectral transmission measurement<\/li>\n\n\n\n<li>Spectral reflection measurement<\/li>\n\n\n\n<li>Coating uniformity evaluation<\/li>\n\n\n\n<li>Adhesion testing<\/li>\n\n\n\n<li>Environmental durability testing<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Visual coating defects may include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Pinholes<\/li>\n\n\n\n<li>Stains<\/li>\n\n\n\n<li>Color non-uniformity<\/li>\n\n\n\n<li>Edge defects<\/li>\n\n\n\n<li>Scratches<\/li>\n\n\n\n<li>Peeling<\/li>\n\n\n\n<li>Cloudiness<\/li>\n\n\n\n<li>\u0e01\u0e32\u0e23\u0e1b\u0e19\u0e40\u0e1b\u0e37\u0e49\u0e2d\u0e19<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The apparent color of an AR coating can change with viewing angle and lighting conditions. A visible color difference does not always mean that the coating is outside specification.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Spectral measurement is more reliable because it directly evaluates optical performance across the specified wavelength range.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For critical orders, coating inspection may be performed at several locations across the clear aperture to confirm uniformity.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">16. Crystal-Orientation Verification<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Sapphire is a single-crystal material with orientation-dependent optical and physical properties.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u0e17\u0e34\u0e28\u0e17\u0e32\u0e07\u0e17\u0e35\u0e48\u0e1e\u0e1a\u0e1a\u0e48\u0e2d\u0e22 \u0e44\u0e14\u0e49\u0e41\u0e01\u0e48:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>C-plane<\/li>\n\n\n\n<li>A-plane<\/li>\n\n\n\n<li>R-plane<\/li>\n\n\n\n<li>M-plane<\/li>\n\n\n\n<li>Custom off-axis orientations<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Orientation may affect:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u0e01\u0e32\u0e23\u0e40\u0e01\u0e34\u0e14\u0e41\u0e2a\u0e07\u0e2a\u0e2d\u0e07\u0e2a\u0e35<\/li>\n\n\n\n<li>Mechanical behavior<\/li>\n\n\n\n<li>\u0e01\u0e32\u0e23\u0e02\u0e22\u0e32\u0e22\u0e15\u0e31\u0e27\u0e17\u0e32\u0e07\u0e04\u0e27\u0e32\u0e21\u0e23\u0e49\u0e2d\u0e19<\/li>\n\n\n\n<li>Machining characteristics<\/li>\n\n\n\n<li>Optical polarization response<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Crystal orientation may be verified using:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>X-ray diffraction<\/li>\n\n\n\n<li>Laue diffraction<\/li>\n\n\n\n<li>Orientation reference marks<\/li>\n\n\n\n<li>Supplier crystal-growth records<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">For general protective windows, orientation may not always be critical. For polarized optical systems, semiconductor equipment and specialized scientific instruments, incorrect orientation can affect performance.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Orientation verification should therefore be included whenever it is specified on the drawing.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">17. Internal Defect Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Although high-quality synthetic sapphire is highly transparent, internal defects may still occur.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Possible internal features include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Bubbles<\/li>\n\n\n\n<li>Inclusions<\/li>\n\n\n\n<li>Growth lines<\/li>\n\n\n\n<li>Color centers<\/li>\n\n\n\n<li>Localized haze<\/li>\n\n\n\n<li>Internal stress<\/li>\n\n\n\n<li>Crystal defects<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Inspection may be carried out using:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Transmitted-light examination<\/li>\n\n\n\n<li>Dark-field illumination<\/li>\n\n\n\n<li>Polarized-light inspection<\/li>\n\n\n\n<li>Optical microscopy<\/li>\n\n\n\n<li>Laser scattering<\/li>\n\n\n\n<li>Imaging systems<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Polarized-light inspection can reveal internal stress patterns or crystal-related optical effects that may not be visible under ordinary lighting.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The acceptance criteria should distinguish between normal crystal characteristics and defects that influence the intended optical function.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">18. Birefringence and Stress Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Sapphire is naturally birefringent because of its crystal structure.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In addition to its inherent birefringence, machining, coating or mounting stress may introduce additional optical retardation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Stress inspection may use crossed polarizers to reveal non-uniform patterns.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This inspection is especially relevant for:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Polarization-sensitive optical systems<\/li>\n\n\n\n<li>\u0e01\u0e32\u0e23\u0e1b\u0e23\u0e30\u0e22\u0e38\u0e01\u0e15\u0e4c\u0e43\u0e0a\u0e49\u0e40\u0e25\u0e40\u0e0b\u0e2d\u0e23\u0e4c<\/li>\n\n\n\n<li>Precision imaging<\/li>\n\n\n\n<li>Bonded sapphire assemblies<\/li>\n\n\n\n<li>Windows exposed to high mechanical load<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A stress pattern does not automatically indicate failure, but strong localized stress near an edge or mounting point may suggest a risk of cracking or optical distortion.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">19. Cleanliness and Particle Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A technically compliant sapphire window can still be rejected if it reaches the customer with dust, oil, fingerprints or packaging residue.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Final cleaning may involve:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Filtered solvents<\/li>\n\n\n\n<li>Ultrasonic cleaning<\/li>\n\n\n\n<li>Deionized-water rinsing<\/li>\n\n\n\n<li>Non-contact drying<\/li>\n\n\n\n<li>Cleanroom wiping<\/li>\n\n\n\n<li>Ionized air<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">After cleaning, the window should be inspected for:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u0e2d\u0e19\u0e38\u0e20\u0e32\u0e04<\/li>\n\n\n\n<li>Fibers<\/li>\n\n\n\n<li>Water marks<\/li>\n\n\n\n<li>Solvent residue<\/li>\n\n\n\n<li>\u0e25\u0e32\u0e22\u0e19\u0e34\u0e49\u0e27\u0e21\u0e37\u0e2d<\/li>\n\n\n\n<li>Adhesive contamination<\/li>\n\n\n\n<li>Packaging debris<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The appropriate cleanliness level depends on the application.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Semiconductor, vacuum and laser components generally require stricter particle control than ordinary protective covers.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Cleaned windows should be handled only with suitable gloves or non-contact tools. Direct contact with the optical surface should be avoided.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">20. Mechanical and Environmental Testing<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Some sapphire windows require additional testing beyond routine dimensional and optical inspection.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Possible tests include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Pressure testing<\/li>\n\n\n\n<li>Vacuum leak testing<\/li>\n\n\n\n<li>Thermal cycling<\/li>\n\n\n\n<li>Temperature exposure<\/li>\n\n\n\n<li>Humidity testing<\/li>\n\n\n\n<li>Mechanical shock<\/li>\n\n\n\n<li>Vibration testing<\/li>\n\n\n\n<li>\u0e01\u0e32\u0e23\u0e17\u0e14\u0e2a\u0e2d\u0e1a\u0e01\u0e32\u0e23\u0e22\u0e36\u0e14\u0e40\u0e01\u0e32\u0e30\u0e02\u0e2d\u0e07\u0e2a\u0e32\u0e23\u0e40\u0e04\u0e25\u0e37\u0e2d\u0e1a<\/li>\n\n\n\n<li>Chemical-resistance testing<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">These tests are normally performed when the sapphire window is part of a completed assembly or when required by the customer.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A sapphire viewport installed in a metal housing may pass all optical inspections but still fail if the seal leaks under pressure or the assembly develops stress during thermal cycling.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">21. Sampling Inspection and Full Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Not every production order requires every dimension to be measured on every part.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The inspection strategy may include:<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Full Inspection<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Every sapphire window is inspected for the specified parameter.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This is commonly used for:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Small quantities<\/li>\n\n\n\n<li>Tight-tolerance components<\/li>\n\n\n\n<li>Laser-grade windows<\/li>\n\n\n\n<li>Aerospace parts<\/li>\n\n\n\n<li>High-value custom products<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Sampling Inspection<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A defined percentage or number of parts is inspected.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This may be suitable for:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Large production batches<\/li>\n\n\n\n<li>Stable manufacturing processes<\/li>\n\n\n\n<li>Standard commercial tolerances<\/li>\n\n\n\n<li>Repetitive products<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Some features, such as severe cracks or shipping contamination, may still require 100% visual inspection even when dimensions are inspected by sampling.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The agreed inspection level should be documented before production.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">22. Inspection Equipment Commonly Used<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A sapphire-window inspection facility may use the following equipment:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>Inspection Item<\/td><td>Typical Equipment<\/td><\/tr><tr><td>Diameter and dimensions<\/td><td>Caliper, micrometer, CMM, vision system<\/td><\/tr><tr><td>Thickness and TTV<\/td><td>Thickness gauge, micrometer, optical gauge<\/td><\/tr><tr><td>Scratch-dig<\/td><td>Inspection lamp, reference standard, microscope<\/td><\/tr><tr><td>\u0e04\u0e27\u0e32\u0e21\u0e40\u0e23\u0e35\u0e22\u0e1a<\/td><td>Optical flat, phase-shifting interferometer<\/td><\/tr><tr><td>\u0e04\u0e27\u0e32\u0e21\u0e2a\u0e21\u0e21\u0e32\u0e15\u0e23<\/td><td>Autocollimator, interferometer, thickness mapping system<\/td><\/tr><tr><td>Surface roughness<\/td><td>Optical profiler, AFM, stylus profilometer<\/td><\/tr><tr><td>Transmission<\/td><td>UV-VIS-NIR or FTIR spectrophotometer<\/td><\/tr><tr><td>\u0e1b\u0e23\u0e30\u0e2a\u0e34\u0e17\u0e18\u0e34\u0e20\u0e32\u0e1e\u0e01\u0e32\u0e23\u0e40\u0e04\u0e25\u0e37\u0e2d\u0e1a<\/td><td>Spectrophotometer or reflectometer<\/td><\/tr><tr><td>\u0e17\u0e34\u0e28\u0e17\u0e32\u0e07\u0e02\u0e2d\u0e07\u0e1c\u0e25\u0e36\u0e01<\/td><td>X-ray diffraction or Laue system<\/td><\/tr><tr><td>Internal defects<\/td><td>Microscope, polarized-light system<\/td><\/tr><tr><td>Cleanliness<\/td><td>Inspection light, microscope, particle counter<\/td><\/tr><tr><td>Edge geometry<\/td><td>Tool microscope, profile projector, vision system<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">The selected equipment should have sufficient accuracy and resolution for the specified tolerance.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">23. Inspection Records and Quality Documents<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Customers may require different levels of quality documentation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Common documents include:<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Certificate of Conformance<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A Certificate of Conformance confirms that the supplied product complies with the purchase order and drawing.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Material Certificate<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">This may identify the sapphire material, crystal orientation, production batch and relevant raw-material information.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Dimensional Inspection Report<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">This report records measured values for diameter, thickness, TTV, chamfer and other dimensions.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Optical Inspection Report<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">This may include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Scratch-dig result<\/li>\n\n\n\n<li>Flatness map<\/li>\n\n\n\n<li>Transmitted wavefront result<\/li>\n\n\n\n<li>\u0e04\u0e27\u0e32\u0e21\u0e2a\u0e21\u0e21\u0e32\u0e15\u0e23<\/li>\n\n\n\n<li>Surface roughness<\/li>\n\n\n\n<li>Transmission curve<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Coating Report<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A coating report may show measured transmission or reflection across the required wavelength range.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Traceability Record<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">For regulated or high-reliability applications, the manufacturer may record the relationship among:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Raw-material lot<\/li>\n\n\n\n<li>Production batch<\/li>\n\n\n\n<li>Inspection data<\/li>\n\n\n\n<li>Coating batch<\/li>\n\n\n\n<li>Packaging label<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The required documentation should be confirmed before production because advanced reports can involve additional testing time and cost.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">24. Final Packaging Inspection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Inspection does not end when the sapphire window passes optical testing.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Packaging must protect the window during storage and transportation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The final packaging check should confirm:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Optical surfaces are clean<\/li>\n\n\n\n<li>Protective materials do not contact or abrade coated areas<\/li>\n\n\n\n<li>Individual windows are separated<\/li>\n\n\n\n<li>Edges are protected<\/li>\n\n\n\n<li>Packaging is free from particles<\/li>\n\n\n\n<li>Labels match the order<\/li>\n\n\n\n<li>Quantity is correct<\/li>\n\n\n\n<li>Inspection reports are included<\/li>\n\n\n\n<li>Outer packaging can withstand transportation<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Typical packaging methods include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Individual clean bags<\/li>\n\n\n\n<li>Lens tissue<\/li>\n\n\n\n<li>Foam-separated trays<\/li>\n\n\n\n<li>Plastic optical boxes<\/li>\n\n\n\n<li>Vacuum-sealed clean packaging<\/li>\n\n\n\n<li>Double-layer protective cartons<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Packaging material should not release fibers, plasticizers or adhesive residue onto the optical surface.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For coated or polished sapphire windows, movement inside the package should be minimized.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">25. Common Causes of Shipment Rejection<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Sapphire windows are commonly rejected for reasons such as:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Dimensions outside tolerance<\/li>\n\n\n\n<li>Excessive scratches or digs<\/li>\n\n\n\n<li>Edge chips entering the clear aperture<\/li>\n\n\n\n<li>Incorrect chamfer<\/li>\n\n\n\n<li>High TTV<\/li>\n\n\n\n<li>Poor flatness<\/li>\n\n\n\n<li>Excessive wedge<\/li>\n\n\n\n<li>Incorrect coating spectrum<\/li>\n\n\n\n<li>Coating scratches<\/li>\n\n\n\n<li>Wrong crystal orientation<\/li>\n\n\n\n<li>Surface contamination<\/li>\n\n\n\n<li>Incomplete inspection documentation<\/li>\n\n\n\n<li>Packaging damage<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Many of these problems can be prevented by reviewing the drawing before manufacturing and defining the inspection method clearly.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">26. What Buyers Should Confirm Before Ordering<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">To reduce inspection disputes, buyers should provide the following information:<\/p>\n\n\n\n<ol start=\"1\" class=\"wp-block-list\">\n<li>Sapphire orientation<\/li>\n\n\n\n<li>Overall dimensions and tolerances<\/li>\n\n\n\n<li>Thickness and TTV<\/li>\n\n\n\n<li>\u0e23\u0e39\u0e23\u0e31\u0e1a\u0e41\u0e2a\u0e07<\/li>\n\n\n\n<li>Scratch-dig requirement<\/li>\n\n\n\n<li>Flatness and reference wavelength<\/li>\n\n\n\n<li>Parallelism or wedge<\/li>\n\n\n\n<li>Surface roughness<\/li>\n\n\n\n<li>Coating wavelength and angle of incidence<\/li>\n\n\n\n<li>Transmission requirement<\/li>\n\n\n\n<li>Edge and chamfer specification<\/li>\n\n\n\n<li>Internal-defect limits<\/li>\n\n\n\n<li>Cleanliness requirement<\/li>\n\n\n\n<li>Sampling or full inspection<\/li>\n\n\n\n<li>Required certificates and reports<\/li>\n\n\n\n<li>\u0e02\u0e49\u0e2d\u0e01\u0e33\u0e2b\u0e19\u0e14\u0e40\u0e01\u0e35\u0e48\u0e22\u0e27\u0e01\u0e31\u0e1a\u0e1a\u0e23\u0e23\u0e08\u0e38\u0e20\u0e31\u0e13\u0e11\u0e4c<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">A complete specification helps the manufacturer select suitable processing and inspection methods from the beginning.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u0e2a\u0e23\u0e38\u0e1b<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Pre-shipment inspection of sapphire windows is a multi-stage quality-control process involving material verification, dimensional measurement, surface evaluation, optical testing, cleanliness control and packaging inspection.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">No single test can completely describe sapphire-window quality.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Visual inspection identifies localized defects, dimensional inspection confirms assembly fit, interferometry evaluates surface form, spectrophotometry measures optical performance, and crystal-orientation testing verifies material alignment.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The appropriate inspection plan should be based on the actual application rather than applying the strictest available tolerance to every window.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">By defining the clear aperture, applicable standards, measurement methods and required reports before production, buyers and manufacturers can reduce ambiguity and ensure that sapphire windows arrive ready for integration into optical, semiconductor, laser, vacuum and high-pressure systems.<\/p>","protected":false},"excerpt":{"rendered":"<p>Sapphire windows are used in optical instruments, semiconductor equipment, laser systems, pressure vessels, aerospace sensors and other applications where both optical transparency and mechanical durability are required. Before shipment, a sapphire window must be inspected to verify that its dimensions, surface condition, optical performance and packaging comply with the customer\u2019s drawing and purchase specification. This [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":2677,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[17],"tags":[1072,1073,152,1069,606,1071,54,1019,1070],"class_list":["post-2676","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-industry-news","tag-optical-component-inspection","tag-optical-quality-control","tag-optical-sapphire-window","tag-pre-shipment-inspection","tag-sapphire-glass-window","tag-sapphire-quality-inspection","tag-sapphire-window","tag-sapphire-window-inspection","tag-sapphire-window-quality-control"],"_links":{"self":[{"href":"https:\/\/www.sapphire-windows.com\/th\/wp-json\/wp\/v2\/posts\/2676","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.sapphire-windows.com\/th\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.sapphire-windows.com\/th\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.sapphire-windows.com\/th\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sapphire-windows.com\/th\/wp-json\/wp\/v2\/comments?post=2676"}],"version-history":[{"count":1,"href":"https:\/\/www.sapphire-windows.com\/th\/wp-json\/wp\/v2\/posts\/2676\/revisions"}],"predecessor-version":[{"id":2678,"href":"https:\/\/www.sapphire-windows.com\/th\/wp-json\/wp\/v2\/posts\/2676\/revisions\/2678"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.sapphire-windows.com\/th\/wp-json\/wp\/v2\/media\/2677"}],"wp:attachment":[{"href":"https:\/\/www.sapphire-windows.com\/th\/wp-json\/wp\/v2\/media?parent=2676"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sapphire-windows.com\/th\/wp-json\/wp\/v2\/categories?post=2676"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sapphire-windows.com\/th\/wp-json\/wp\/v2\/tags?post=2676"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}