Product type: Thin Film Filter. Application: Lighting, Medical, Optical, Photography, Astronomy. Model: Filter.
Overview
Dia21mm Multi-Layer Dielectric Coating Optical Longpass Filter: a longpass / shortpass filter made from Fused Silica. Listed geometry: diameter 21.0+/-0.1mm, thickness 3.0+0.0/-0.1mm, round shape. Coating: Multi-layer dielectric coating,extend to within at least 1.0mm from circumference,surface B; surface quality 40-20; flatness 1/4L PTV,TWD. It is used in Lighting, Medical, Optical, Photography and Astronomy. Dimensions, material grade, coating and finish can be quoted to your drawing; the values above are the listed starting point.
Specifications
| Material | Fused Silica |
|---|---|
| Type | Thin Film Filter |
| Shape | Round |
| Diameter | 21.0+/-0.1mm |
| Thickness | 3.0+0.0/-0.1mm |
| Coating | Multi-layer dielectric coating,extend to within at least 1.0mm from circumference,surface B |
| Surface quality | 40-20 |
| Flatness | 1/4L PTV,TWD |
| Parallelism | <20arcsec |
| Clear aperture | 1.5mm from the circumference |
| Usage | Lighting, Medical, Optical, Photography, Astronomy |
| Model NO. | Filter |
| Thickness Range | 2mm-5mm |
| Color | Transparent |
| Principle | Cut-off Filter |
| Angle of incidence | 45° |
| R1 | infinity |
| R2 | infinity |
| Chamfer | 0.2mmx45deg |
| Tavg>85%@470-1750nm,AOI | 0deg,total filter |
| Standard | MIL-PRF-13830B |
| https | //cpgoptics.en.made-in-china.com/product/gCxncWjUhhVD/China-Customized-Fluorescence-Optical-Dichroic-Longpass-Filter.html |
| Supplier | CPG OPTICS LIMITED |
Technical data
| Items | Description | |
| Filter | Material: | UV Fused Silica |
| Diameter: | 21.0+/-0.1mm | |
| Thickness: | 3.0+0.0/-0.1mm | |
| R1: | infinity | |
| R2: | infinity | |
| Flatness: | 1/4L PTV,TWD | |
| Surface quality: | 40-20 | |
| Parallelism: | <20arcsec | |
| Clear aperture: | 1.5mm from the circumference | |
| Chamfer: | 0.2mmx45deg | |
| <1.0mm,chips of edges | ||
| Coating: | Multi-layer dielectric coating,extend to within at least 1.0mm from circumference,surface B | |
| 470-2000nm,transmission waveband,surface B | ||
| 200-430nm,rejection waveband,surface B | ||
| 3%,slope factor,surface B | ||
| 450+/-10nm,cut-on wavelength,surface B | ||
| Standard: | MIL-PRF-13830B |
What to specify when you request a quote
- Spectral target — state the centre or edge wavelength, the bandwidth and the minimum transmission in the passband.
- Blocking — give the blocking range and optical density (OD) the system needs.
- Angle of incidence — listed as “45°”; interference filters shift with angle, so specify the operating angle and cone.
- Size and thickness — listed as “21.0+/-0.1mm”; give outline, thickness and tolerance, and whether the filter is mounted.
- Substrate — listed as “Fused Silica”; name the substrate glass if thermal or UV behaviour matters.
- Surface quality — listed as “40-20”; quote scratch-dig for imaging paths.
Engineering guides for this part
For material grades and coating options, see Selecting Longpass Filter Glass for Precision Optical Systems. How parts like this are machined and finished is covered in Precision CNC Machining of Quartz & Fused Silica Components. For an application example, read Custom Shortpass Filter Glass for Appliance Optical Modules. Before sending a drawing, check Fused Silica Refractive Index: Key to Optical Design Improvement. A related standard product is Shortpass Filter.
