Solid Silicon Etalons

Germanium; 2.5-14 µm; Finesse Dependent on Wavelength; FSR Dependent on Wavelength; Thickness 25.4-50.8 mm; Uncoated; Dia 25.4 mm; Clear Aperture Dia. 12.7 mm LightMachinery’s OP-5483 series of solid Germanium (Ge) etalons are high-index components for longer IR wavelengths. OP-5483 series etalons are manufactured using the company’s patented fluid jet polishing (FJP) technology – allowing the adjustment of the etalon’s shape and flatness to within a few nanometers. This series of thick Germanium etalons is available with a diameter of 25.4 mm and lengths of 25.4, 38 and 50.8 mm. Germanium etalons have a high index (~4.0 depending on wavelength) that creates a reasonably high finesse without any coatings. They also remain transmissive farther out into the infrared than silicon etalons and will still provide a decent signal at a wavelength of 14 µm. The high temperature sensitivity of Germanium is similar to Silicon and can also be useful (or problematic). These etalons are often used to monitor the wavelengths of tunable lasers (like lead salt or quantum cascade lasers) in the mid-infrared. A portion of the output from your tunable laser is directed at the Germanium etalon. As the laser is tuned, the transmission through the etalon is modulated with a spacing between transmission peaks equal to the etalon’s FSR. As Germanium is very temperature sensitive, OP-5483 series etalons are not very useful for determining the absolute wavelength, but by tracking the number of peaks from a reference, the relative wavelength can be determined quite accurately. Etalons are optically transparent, flat components with very precisely parallel reflecting surfaces. For high performance (i.e. resolution), these components require very high-quality, flat and level surfaces with low roughness and extreme parallelism. Solid Germanium etalons are comparatively simple, robust, yet very parallel optical components with a wide variety of applications in lasers and spectroscopy. Although solid etalons are generally coated to increase the finesse of the etalon, uncoated solid etalons like the OP-5483 series – using only the 4% fresnel reflection to provide the etalon effect –are often used inside laser cavities since only low finesse is required to filter out unwanted laser wavelengths, and uncoated etalons are very damage resistant. One major issue with solid etalons is their instability to temperature changes (both the index and the physical thickness of the etalon material change with temperature), which can be unacceptable in certain applications. In those cases, please refer to air spaced etalons that reduce this problem of temperature dependence by using air as the etalon medium. In certain applications though, the temperature dependence can also be a useful method for tuning the transmission peak position since it effectively changes the thickness of the etalon. Sometimes you need something special – if you are looking for a customized solid Germanium etalon that exactly meets your specific requirements, please get in touch with the AMS Technologies etalon experts. Our supplier LightMachinery is extremely experienced with specifying, designing and manufacturing custom etalons using the company’s patented fluid jet polishing (FJP) technology. We are looking forward to discussing your customized etalon solution! Fluid jet polishing (FJP) systems use a fine stream of slurry to accurately remove nanometers of material from an optical surface. Many years of refining this computer controlled polishing technology have enabled LightMachinery to use FJP for the adjustment of the shape and flatness of optical components such as etalon mirrors to within a few nanometers as well as the production of very thin components such as wafers and thin etalons that are impossible to accurately polish using conventional technology. Key Features: Etalon Material: Germanium Wavelength Range: 2.5 to 14 µm (Infrared, IR) Finesse: Dependent on Wavelength Free Spectral Range, FSR: Dependent on Wavelength Uncoated Diameter: 25.4 mm (1”) Length: 25.4, 38, 50.8 mm Clear Aperture: Diameter 12.7 mm Surface Figure: λ/10 Surface Quality: 80/50 or Better Wedge: <0.5 arcsec – If Coating is Required, Wedge Can Be Reduced and Finesse Can Be Increased Applications: Spectroscopy; Lasers; Interferometers; Wavelength Measurement; Fine-structural Investigation of Spectral Lines

Fused Silica, CaF2; 415-1700 nm, Customer Specified; Finesse 56-~100, Customer Specified; FSR 15-60 GHz, 0.5-2/cm, Customer Specified; Thickness 1.68-6.74 mm, Customer Specified; AR and HR Coating; 22.0x24.0, Customer Specified; Clear Aperture 18x18 mm, Customer Specified LightMachinery’s OP-6721/OP-7553 series of VIPA (Virtually Imaged Phase Array) etalons are manufactured from Fused Silica (OP-6721) or Calcium Fluoride (OP-7553), allowing operation further into the infrared, IR) using the company’s patented fluid jet polishing (FJP) technology – allowing the adjustment of the etalon’s shape and flatness to within a few nanometers. Catalog series OP-6721 VIPA etalons are available with dimensions of 22.0 x 24.0 mm and 18 x 18 mm aperture. Free spectral range (FSR) values are 15 GHz (0.5/cm), 30 GHz (1/cm) and 60 GHz (2/cm), each available with nine different finesse values from 56 to 100, resulting in nine different wavelength ranges from 415 to 1700 nm. Wavelength range, thickness, finesse, FSR and other design details of OP-6721 and OP-7553 series VIPAs are also available based on customer requirements. For the OP-6271 series, a dedicated protective aluminium mount is available that enables mounting the VIPA in a standard 50.8 mm (2”) diameter optic holder – its price includes cementing of the VIPA to the mount at the supplier. A VIPA (Virtually Imaged Phase Array) is a special type of Fabry-Perot etalon with a built-in transmission window so the beam can sneak in past the first reflector and effectively commence the multiple reflections and constructive and destructive interference from inside the etalon. By changing the first reflector to a full 100% high reflector, the beam can only exit in transmission, this effectively creates an etalon with ~100% transmission. VIPAs are made with three distinct coatings, carefully selected to match the wavelength range of interest: One surface of a VIPA has an anti-reflection coated section adjacent to a high reflector. The opposite surface is coated with a partially transmitting mirror. Light is introduced into the VIPA at a small angle on the AR coated area. The VIPA is tilted so that the portion reflected from the partial reflector is fully incident on the high reflectance zone of the input surface. A single input beam is converted to a series of parallel output beams of gradually decreasing intensity. These beams will constructively interfere at an angle that depends on the wavelength. Placing a lens between the VIPA and an array detector (CCD or similar) allows recording of a spectrum of the input light. Each subsequent beam has a precise increase in phase and fixed lateral displacement, hence “phase array”. LightMachinery is the world leader in high-accuracy VIPA fabrication, and VIPAs are at the core of many of LightMachinery’s spectrometers. Several parameters define the performance of a VIPA. The first is its optical thickness (OPD) – the free spectral range (FSR) is approximately c/OPD. Analogous to a regular etalon, the angular dispersion of the VIPA output will repeat every time the input frequency (or wavelength) increases by 1 FSR. The second important parameter is the reflectance of the output mirror. In principle, a higher reflectance mirror will increase the resolving power of the VIPA. Light Machinery has optimized the partial reflectivity for each wavelength range to maximize finesse; finesse greater than 100 has been achieved for VIS/NIR applications. In other words, it will be possible to distinguish wavelengths separated by 1/100th of the FSR. The third important parameter is the internal angle of the light traveling through the VIPA. Smaller angles increase the angular dispersion, and a narrower transition between the antireflection coating and the high reflector enables a smaller angle. LightMachinery’s VIPAs have a transition width of only 2 to 3 µm, which enables operation of the VIPA at a very small angle. This reduction in angle improves resolution and contrast compared to what was previously possible. Sometimes you need something special – if you are looking for a customized VIPA etalon that exactly meets your specific requirements (e.g. different substrate materials like Silicon, etc.), please get in touch with the AMS Technologies etalon experts. Our supplier LightMachinery is extremely experienced with specifying, designing and manufacturing custom etalons using the company’s patented fluid jet polishing (FJP) technology. We are looking forward to discussing your customized etalon solution! Fluid jet polishing (FJP) systems use a fine stream of slurry to accurately remove nanometers of material from an optical surface. Many years of refining this computer controlled polishing technology have enabled LightMachinery to use FJP for the adjustment of the shape and flatness of optical components such as etalon mirrors to within a few nanometers as well as the production of very thin components such as wafers and thin etalons that are impossible to accurately polish using conventional technology. Key Features: VIPA (Virtually Imaged Phase Array) Etalons Etalon Material: Fused Silica (OP-6721) or Calcium Fluoride (OP-7553) Anti-reflective (AR) and High-reflection (HR) Coating Wavelength Range: 415 to 1700 nm or Customer Specified Finesse: 56 to ~100 or Customer Specified Free Spectral Range, FSR: 15, 30, 60 GHz (2/cm, 1/cm, 0.5/cm) or Customer Specified Dimensions: 22.0 x 24.0 mm Including a 3 mm Input Window or Customer Specified Thickness: 1.68 to 8.74 mm or Customer Specified Clear Aperture: 18 x 18 mm or 90% of Outside Dimensions Matched Surface Figure: λ/200 rms Surface Quality: 10/5 or Better Substrate Wedge: <0.05 arcsec Applications: Spectroscopy; Interferometers; Wavelength Measurement; Lasers; Fine-structural Investigation of Spectral Lines

Fused Silica, Zerodur; Wavelength Range Customer Specified; Finesse Customer Specified; FSR Customer Specified; AR-coated; Dia. 25.4-203.2 mm; Clear Aperture 5-150 mm LightMachinery’s OP-740x series of air spaced etalons is manufactured using the company’s patented fluid jet polishing (FJP) technology – allowing the adjustment of the etalon’s shape and flatness to within a few nanometers. OP-740x air spaced etalons are available in eight sizes with diameters from 25.4 (1”) to 203.2 mm (8”) and apertures from 5 to 150 mm. Wavelength range, finesse, free spectral range (FSR) and design details can be realized based on customer requirements. Etalons are optically transparent, flat components with very precisely parallel reflecting surfaces. While solid etalons consist of solid plates of optical material, air spaced etalons are formed by two mirrors with an air gap between them. One major issue with solid etalons is their instability to temperature changes, which can be unacceptable in certain applications. Air spaced etalons reduce this problem of temperature dependence by using air as the etalon medium to greatly reduce the change in refractive index with temperature. The mirror spacing is now determined by spacers that may still be made from Fused Silica or from even more stable materials such as ULE or Zerodur. Due to their construction, air spaced etalons are significantly more complex since there are now three components involved (two end mirrors and the spacer). The outside surfaces of the end mirrors also need to be wedged and AR-coated to avoid reflections from these surfaces causing additional unwanted etalon effects. Sometimes you need something special – if you are looking for a customized air spaced etalon that exactly meets your specific requirements, please get in touch with the AMS Technologies etalon experts. Our supplier LightMachinery is extremely experienced with specifying, designing and manufacturing custom etalons using the company’s patented fluid jet polishing (FJP) technology. We are looking forward to discussing your customized etalon solution! Fluid jet polishing (FJP) systems use a fine stream of slurry to accurately remove nanometers of material from an optical surface. Many years of refining this computer controlled polishing technology have enabled LightMachinery to use FJP for the adjustment of the shape and flatness of optical components such as etalon mirrors to within a few nanometers as well as the production of very thin components such as wafers and thin etalons that are impossible to accurately polish using conventional technology. Key Features: Etalon Material: Standard Material is Fused Silica, However Zerodur May Be Specified Wavelength Range: Customer Specified Finesse: Customer Specified Free Spectral Range, FSR: Customer Specified AR-coated: Less Than 0.5% Reflection Diameter: 25.4 to 203.2 mm Clear Aperture: 5 to 150 mm Resonator Surface Figure Matching: λ/100 or Better Front Surface Figure: λ/20 or Better Surface Quality: 10/5 or Better Wedge: 30 arcmin (To Avoid Reflections) Applications: Spectroscopy; Interferometers; Wavelength Measurement; Fine-structural Investigation of Spectral Lines

Zinc Selenide; 0.6-20 µm; Finesse ~1.6, Dependent on Wavelength; FSR Dependent on Wavelength; Thickness 0.5, 1.0, 2.0 mm; Uncoated; Dia. 12.7 mm; Clear Aperture Dia. 8 mm LightMachinery’s OP-7894 series of solid Zinc Selenide (ZnSe) etalons are very wide wavelength range, low-finesse etalons components with a reasonably high index (~2.5 depending on wavelength) that creates a reasonably high finesse without any coatings. Zinc Selenide etalons also remain transmissive over a very broad wavelength range from 600 nm to 20 µm. Thermal tuning is high but not as rapid as Silicon or Germanium. Unfortunately Zinc Selenide is one of the few optical materials that cannot be fluid jet polished (due to the grain structure), so LightMachinery cannot make the parallelism super uniform and coat the ZnSe devices to create high-finesse etalons. But for low-finesse (~1.6) etalons that work over a massive wavelength range, the OP-7894 devices – available with a diameter of 12.7 mm and 0.5, 1.0 or 2.0 mm thickness – are pretty handy. Etalons are optically transparent, flat components with very precisely parallel reflecting surfaces. For high performance (i.e. resolution), these components require very high-quality, flat and level surfaces with low roughness and extreme parallelism. Solid Zinc Selenide etalons are comparatively simple, robust, yet very parallel optical components with a wide variety of applications in lasers and spectroscopy. Although solid etalons are generally coated to increase the finesse of the etalon, uncoated solid etalons like this series – using only the 4% fresnel reflection to provide the etalon effect – are often used inside laser cavities since only low finesse is required to filter out unwanted laser wavelengths, and uncoated etalons are very damage resistant. One major issue with solid etalons is their instability to temperature changes (both the index and the physical thickness of the etalon material change with temperature), which can be unacceptable in certain applications. In those cases, please refer to air spaced etalons that reduce this problem of temperature dependence by using air as the etalon medium. In certain applications though, the temperature dependence can also be a useful method for tuning the transmission peak position since it effectively changes the thickness of the etalon. Sometimes you need something special – if you are looking for a customized solid ZnSe etalon that exactly meets your specific requirements, please get in touch with the AMS Technologies etalon experts. Our supplier LightMachinery is extremely experienced with specifying, designing and manufacturing custom etalons. We are looking forward to discussing your customized etalon solution! Key Features: Etalon Material: Zinc Selenide (ZnSe) Wavelength Range: 0.6 to 20 µm (Red to LR) Finesse: ~1.6, Dependent on Wavelength Free Spectral Range, FSR: Dependent on Wavelength Uncoated Diameter: 12.7 mm (1/2") Thickness: 0.5, 1.0, 2.0 mm Clear Aperture: Diameter 8 mm Surface Figure: λ/50 Transmitted Wavefront Error: λ/8 Surface Quality: 40/20 or Better Wedge: <2.5 arcsec Applications: Lasers; Spectroscopy; Interferometers; Wavelength Measurement; Fine-structural Investigation of Spectral Lines

Fused Silica; 350-900 nm; Finesse ~2.5, Dependent on Wavelength; FSR 0.5-2/cm; Thickness 1.686-6.743 mm; Broadband Metallic Coating; Dia. 25.4 mm; Clear Aperture Dia. 20.0 mm LightMachinery’s OP-8565 series of solid Fused Silica etalons with broadband metallic coatings (Metalons) are manufactured using the company’s patented fluid jet polishing (FJP) technology – allowing the adjustment of the etalon’s shape and flatness to within a few nanometers. These very broadband (350 to 900 nm), low-finesse metalons are available with a diameter of 25.4 mm and 1.686, 3.371 or 6.743 mm thickness. Corresponding free spectral range (FSR) values are 2/cm, 1/cm and 0.5/cm respectively. It is very difficult to create very broadband dielectric coatings, however metal coatings are naturally effective over a wide range of wavelengths. Sadly, they also absorb a significant amount of energy and as the reflectivity is pushed higher, the absorption also increases. LightMachinery’s metal coated etalons, or Metalons, are a compromise that achieves a reasonable finesse of about 2.5 using coatings that are about between 30% and 40% reflective from 350 to 900 nm. The result is a peak transmission of about 40%, so if you need really high transmission and no loss then this is not your etalon. But the modulation is about 75%, so if your application calls for wavelength monitoring, OP-8656 metalons might just work great and will almost certainly work for your wavelength range. Etalons are optically transparent, flat components with very precisely parallel reflecting surfaces. For high performance (i.e. resolution), these components require very high-quality, flat and level surfaces with low roughness and extreme parallelism. Metal-coated Solid Fused Silica etalons are comparatively simple, robust, yet very parallel optical components with a wide variety of applications in lasers and spectroscopy. One major issue with solid etalons is their instability to temperature changes (both the index and the physical thickness of the etalon material change with temperature), which can be unacceptable in certain applications. In those cases, please refer to air spaced etalons that reduce this problem of temperature dependence by using air as the etalon medium. In certain applications though, the temperature dependence can also be a useful method for tuning the transmission peak position since it effectively changes the thickness of the etalon. Sometimes you need something special – if you are looking for a customized metal-coated solid Fused Silica etalon that exactly meets your specific requirements, please get in touch with the AMS Technologies etalon experts. Our supplier LightMachinery is extremely experienced with specifying, designing and manufacturing custom etalons using the company’s patented fluid jet polishing (FJP) technology. We are looking forward to discussing your customized etalon solution! Fluid jet polishing (FJP) systems use a fine stream of slurry to accurately remove nanometers of material from an optical surface. Many years of refining this computer controlled polishing technology have enabled LightMachinery to use FJP for the adjustment of the shape and flatness of optical components such as etalon mirrors to within a few nanometers as well as the production of very thin components such as wafers and thin etalons that are impossible to accurately polish using conventional technology. Key Features: Etalon Material: Fused Silica, 7980 OA Grade Broadband Metallic Coating Wavelength Range: 350 to 900 nm Finesse: ~2.5, Dependent on Wavelength Free Spectral Range, FSR: 2/cm, 1/cm, 0.5/cm Diameter: 25.4 mm (1") Thickness: 1.686, 3.371, 6.743 mm Clear Aperture: Diameter 20.0 mm Surface Figure: λ/10 Surface Quality: 80/50 or Better Thickness Uniformity (Wedge) <2 nm rms Over the Clear Aperture Applications: Wavelength Monitoring; Lasers; Spectroscopy; Interferometers; Wavelength Measurement; Fine-structural Investigation of Spectral Lines

Fused Silica; 450-1700 nm; Finesse 0.6, 6, >30; FSR 20-4023 GHz, 0.5-2/cm; Thickness 0.025-6.743 mm; Uncoated or Coated; 2x4, 5x5, Dia. 25.4 mm; Clear Aperture Dia. 20 mm LightMachinery’s broad range of solid Fused Silica (SiO2) etalons is manufactured using the company’s patented fluid jet polishing (FJP) technology – allowing the adjustment of the etalon’s shape and flatness to within a few nanometers. LightMachinery’s Fused Silica etalons are available uncoated in rectangular shapes with dimensions of 2 x 4 or 5 x 5 mm or with dielectric coatings in circular shapes and 25.4 mm diameter. Uncoated 2 x 4 mm solid Fused Silica etalons are very small devices that our customers usually cement on one end to a holder. The small size is preferred for use inside small laser cavities. A dedicated 12.7 mm diameter aluminium mount designed to hold 2 x 4 mm etalons is available – its price includes cementing of the etalon to the mount at the supplier. Uncoated 5 x 5mm solid Fused Silica etalons are slightly larger versions that are easier to manipulate with human hands. Again, a dedicated 25.4 mm diameter mount designed to hold 5 x 5 mm etalons is available – its price including cementing of the etalon to the mount at the supplier. While uncoated, rectangular types feature a finesse of 0.6, circular 25.4 mm (1”) diameter solid Fused Silica etalons with dielectric coatings for higher finesse are available for five different wavelength ranges (450 to 650, 530 to 660, 700 to 850, 850 to 1100, 1450 to 1700 nm) and with finesse values of 6 or >30. Etalons are optically transparent, flat components with very precisely parallel reflecting surfaces. For high performance (i.e. resolution), these components require very high-quality, flat and level surfaces with low roughness and extreme parallelism. Solid Fused Silica etalons are comparatively simple, robust, yet very parallel optical components with a wide variety of applications in spectroscopy and lasers. Although solid etalons are generally coated to increase the finesse of the etalon, uncoated solid etalons – using only the 4% fresnel reflection to provide the etalon effect – are often used inside laser cavities since only low finesse is required to filter out unwanted laser wavelengths, and uncoated etalons are very damage resistant. One major issue with solid etalons is their instability to temperature changes (both the index and the physical thickness of the etalon material change with temperature), which can be unacceptable in certain applications. In those cases, please refer to air spaced etalons that reduce this problem of temperature dependence by using air as the etalon medium. In certain applications though, the temperature dependence can also be a useful method for tuning the transmission peak position since it effectively changes the thickness of the etalon. Sometimes you need something special – if you are looking for a customized solid Fused Silica etalon that exactly meets your specific requirements, please get in touch with the AMS Technologies etalon experts. Our supplier LightMachinery is extremely experienced with specifying, designing and manufacturing custom etalons using the company’s patented fluid jet polishing (FJP) technology. We are looking forward to discussing your customized etalon solution! Fluid jet polishing (FJP) systems use a fine stream of slurry to accurately remove nanometers of material from an optical surface. Many years of refining this computer controlled polishing technology have enabled LightMachinery to use FJP for the adjustment of the shape and flatness of optical components such as etalon mirrors to within a few nanometers as well as the production of very thin components such as wafers and thin etalons that are impossible to accurately polish using conventional technology. Key Features: Etalon Material: Fused Silica Wavelength Range: 450 to 1700 nm Finesse: 0.6, 6, >30 Free Spectral Range, FSR: 20 to 4023 GHz, 0.5/cm to 2/cm Coating: Uncoated or Dielectric Coating Rectangular Types: 2 x 4, 5 x 5 mm Dedicated 12.7 or 25.4 mm Diameter Aluminium Mounts Available for Rectangular Types – Price Includes Cementing of the Etalon to the Mount at the Supplier Circular Types: Diameter 25.4 mm (1”) Clear Aperture: 85% of Outside Dimension (Diameter 20 mm for Circular Types) Matched Surface Figure: λ/100 Surface Quality: 10/5 or Better Wedge: 0.1 arcsec Typical Applications: Spectroscopy; Lasers; Interferometers; Wavelength Measurement; Fine-structural Investigation of Spectral Lines

Undoped YAG; 250-4000 nm; Finesse ~1, Dependent on Wavelength; FSR ~0.8-3300 GHz, Dependent on Wavelength; Thickness 0.025-98.0 mm; Uncoated; Dia. 5, 12.7 mm; Clear Aperture Dia. 3, 10 mm LightMachinery’s series of solid YAG etalons are high-index components manufactured using the company’s patented fluid jet polishing (FJP) technology – allowing the adjustment of the etalon’s shape and flatness to within a few nanometers. Solid YAG etalons are handy because the high index of YAG material (about 1.8 depending on wavelength) creates a reasonably high finesse without any coating; this makes "yagalons" excellent for mode selection in high-power solid state lasers. The additional advantage of YAG is excellent transmission in a wide range of wavelengths (250 nm to 4 µm). These etalons are available in two standard sizes with diameters of 5 and 12.7 mm respectively. Thicknesses range from 25 µ to 1 mm for the smaller and from 0.05 to 98.0 mm for the larger size. Dedicated 12.7 or 25.4 mm diameter aluminium mounts designed to hold the 5 mm diameter etalons are available as well as dedicated 25.4 mm diameter aluminium mounts designed to hold the 12.7 mm diameter etalons – prices for these mounts include cementing of the etalon to the mount at the supplier. Etalons are optically transparent, flat components with very precisely parallel reflecting surfaces. For high performance (i.e. resolution), these components require very high-quality, flat and level surfaces with low roughness and extreme parallelism. Solid YAG etalons are comparatively simple, robust, yet very parallel optical components with a wide variety of applications in lasers and spectroscopy. Although solid etalons are generally coated to increase the finesse of the etalon, uncoated solid etalons like this series – using only the 4% fresnel reflection to provide the etalon effect – are often used inside laser cavities since only low finesse is required to filter out unwanted laser wavelengths, and uncoated etalons are very damage resistant. One major issue with solid etalons is their instability to temperature changes (both the index and the physical thickness of the etalon material change with temperature), which can be unacceptable in certain applications. In those cases, please refer to air spaced etalons that reduce this problem of temperature dependence by using air as the etalon medium. In certain applications though, the temperature dependence can also be a useful method for tuning the transmission peak position since it effectively changes the thickness of the etalon. Sometimes you need something special – if you are looking for a customized solid YAG etalon that exactly meets your specific requirements, please get in touch with the AMS Technologies etalon experts. Our supplier LightMachinery is extremely experienced with specifying, designing and manufacturing custom etalons using the company’s patented fluid jet polishing (FJP) technology. We are looking forward to discussing your customized etalon solution! Fluid jet polishing (FJP) systems use a fine stream of slurry to accurately remove nanometers of material from an optical surface. Many years of refining this computer controlled polishing technology have enabled LightMachinery to use FJP for the adjustment of the shape and flatness of optical components such as etalon mirrors to within a few nanometers as well as the production of very thin components such as wafers and thin etalons that are impossible to accurately polish using conventional technology. Key Features: Etalon Material: Undoped YAG Wavelength Range: 250 to 4000 nm Finesse: ~1, Dependent on Wavelength Free Spectral Range, FSR: ~0.8 to 3300 GHz (Based on Index 1.82), Dependent on Wavelength Uncoated Diameter: 5.0, 12.7 mm (1/2") Thickness: 0.025 to 98.0 mm Dedicated 12.7 or 25.4 mm Diameter Aluminium Mounts Available – Price Includes Cementing of the Etalon to the Mount at the Supplier Clear Aperture: Diameter 3, 10 mm (85% of Outside Dimension) Surface Figure: λ/50 Surface Quality: 10/5 or Better Wedge: <1 arcsec Typical Applications: Mode Selection in High-power Solid State Lasers; Spectroscopy; Interferometers; Wavelength Measurement; Fine-structural Investigation of Spectral Lines