Custom Witness Sample Fabrication
Best practices suggest that when coating or setting up an optical component, it’s best to use a witness sample, also called a “test piece,” to ensure that the actual part will match your specific coating specifications and your application.
Sydor Optics also offers witness samples for the measurement of coating stresses on substrates. The size and thickness of a witness sample will typically match your finished product.
- Test samples available before the commitment of a high-volume run
Available Material Types
Based upon customer demand, Sydor Optics offers Witness Samples made from the following optical substrate materials. Of course, if you don’t see a material you need, please contact a Sales Engineer, who will gladly discuss additional options that may be available.
Color Filter Glass
Colored filter glass is available in a range of spectral characteristics each suited to unique transmission and absorption properties of various wavelengths of light.
- UV Bandpass
- Longpass
- SCHOTT GG395
- SCHOTT GG400
- SCHOTT GG420
- SCHOTT GG435
- SCHOTT GG455
- SCHOTT GG475
- SCHOTT GG495
- SCHOTT N-WG280
- SCHOTT N-WG295
- SCHOTT N-WG305
- SCHOTT N-WG320
- SCHOTT OG515
- SCHOTT OG530
- SCHOTT OG550
- SCHOTT OG570
- SCHOTT OG590
- SCHOTT RG1000
- SCHOTT RG610
- SCHOTT RG630
- SCHOTT RG645
- SCHOTT RG665
- SCHOTT RG695
- SCHOTT RG715
- SCHOTT RG780
- SCHOTT RG830
- SCHOTT RG850
- SCHOTT RG9
- Shortpass
- Multiband
- Color Compensating – Cyan
- Light Balancing – Amber
- Light Balancing – Blue
- UV Transmitting / VIS Absorbing
- UV Transmitting
- UV Sharp Cut
- Color Compensating – Blue
- Light Balancing
Popular MaterialsCrystal
Optical crystals are glass-like materials grown from high-purity raw materials. The most common crystals include calcium fluoride—effective for UV-spectrum applications—and magnesium fluoride, which is useful for mid-wave IR applications.
Popular MaterialsDisplay Glass
Borosilicate glass, also called display glass, offers a combination of excellent light transmission and impressive technical properties. Made of silicon oxide and boron oxide, display glass is easily laser- or CNC-machined. In addition to having excellent chemical resistance, the material possesses a low coefficient of thermal expansion, meaning that it can resist high temperatures without cracking.- Corning EAGLE XG
- Pilkington Optiwhite
- SCHOTT B 270 i Ultra-White Glass
- SCHOTT BOROFLOAT 33
- SCHOTT D 263 T eco
- SCHOTT OPALIKA
- SCHOTT SUPREMAX 33
Popular MaterialsFused Quartz
Fused Quartz is made using high quality, natural quartz powders with several fusion methods. Quartz material is stronger than glass, can be used at high temperatures (<1050°C) and has a high average transmission of over 80% from 260nm to 2500nm. The various qualities of fused quartz allow for use in a wide range of applications from semiconductor applications to lower precision window applications in hostile environments.- Heraeus HOQ 310
- Heraeus INFRASIL 301, 302
- Heraeus TSC Series
- Momentive i21 (Previously GE 124)
- Ohara SK-4304, SK-4306
- Tosoh N, OP, S Series
Popular MaterialsFused Silica
Fused silica is a transparent glass formed by melting and cooling pure silica sand. Unlike most other glasses, fused silica does not contain any additives. It is an amorphous solid with a purity that gives it excellent optical transmission.- Corning HPFS 7979 (UV & IR Grades)
- Corning HPFS 7980 (ArF Grade)
- Corning HPFS 7980 (KrF Grade)
- Corning HPFS 7980 (Standard Grade)
- Corning HPFS 8655
- Heraeus HOMOSIL 101, HERASIL 102
- Heraeus SUPRASIL 1, 2 (Grade A & B)
- Heraeus SUPRASIL 3001, 3002
- Heraeus SUPRASIL 311, 312
- Heraeus SUPRASIL 313
- Nikon NIFS (V, A, U, S Grade)
- Ohara SK-1300
- Ohara SK-1310
- Ohara SK-1320
- Tosoh ES, ED-H Series
Popular MaterialsIR Materials
Infrared materials produce good transmission in the infrared (IR) spectrum, which spans 0.75 μm to 15µm. Infrared materials are commonly selected for their transmission properties in the NIR (0.75µm – 1µm), SWIR (1µm – 2.7µm), MWIR (3µm – 5µm) or LWIR (8µm – 12µm) spectral sub-regions. The most common IR materials are silicon, germanium, sapphire, zinc sulfide, and zinc selenide.
- Sapphire
- Zinc Selenide
Popular MaterialsOptical Glass
Optical glass is known for its high transmission, low dispersion, and homogenous refraction indices. These properties result from the continuous melting process and subsequent finishing methods used to create optical glass. This material is categorized into either flint glass or crown glass. Flint glass has an Abbe number < 55 and generally < 50. Flint glass is denser due to the inclusion of various metal oxides and exhibits strong chromatic dispersion. Crown glass has an Abbe number> 50 and generally > 55. Crown glass is typically less dense resulting from higher usage of alkali metals and exhibits low chromatic dispersion.- Hoya BSC7
- Ohara S-BSL 7
- Ohara S-TIH1
- Ohara S-TIH10
- Ohara S-TIH11
- Ohara S-TIH4
- Ohara S-TIH6
- Ohara S-TIM22
- Ohara S-TIM25
- Ohara S-TIM28
- SCHOTT BK7G18
- SCHOTT N-BK7
- SCHOTT N-BK7HT
- SCHOTT N-SF1
- SCHOTT N-SF10
- SCHOTT N-SF11
- SCHOTT N-SF2
- SCHOTT N-SF4
- SCHOTT N-SF5
- SCHOTT N-SF6
- SCHOTT N-SF8
Popular Materials
Witness Sample Manufacturing Limits
| Specifications | Measurements |
|---|---|
| Diameter | customer specified (typically 25mm – 50mm) |
| Thickness | customer specified (typically 1mm) |
| Thickness Tolerance | ± 0.01mm |
| Cosmetics (MIL-PRF-13830B) | 60-40 to 20-10 |
| Surface Roughness | ≥ 5 Ǻ rms |
| Reflected Wavefront Error (RWE) – before coating | ≥ 1/10 wave over clear aperture |
| Transmitted Wavefront Error (TWE) – before coating | ≥ 1/10 wave over clear aperture |
| Clear Aperture | ≤ 95% |
If you are starting a new program or need assistance, please contact us.
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