Choose the IR Control Filter for Your Optical System
The main selection starts with which part of the spectrum must pass through the filter and which part must be reflected.
950 Economy Hot Mirror
A visible-pass, near-infrared-reflecting hot mirror for systems that require broad visible transmission with NIR rejection through approximately 950 nm.
- Average transmission: >93% from 425–675 nm
- Average reflection: >95% from 750–950 nm
1150 Hot Mirror
Extends the reflected near-infrared range beyond the 950 economy configuration while maintaining high visible transmission.
- Average transmission: >93% from 425–675 nm
- Average reflection: >95% from 750–1150 nm
1600 Extended Hot Mirror
Designed for systems requiring visible transmission together with reflection extending deeper into the near-infrared region.
- Average transmission: >85% from 425–675 nm
- Average reflection: >90% from 750–1150 nm
- Average reflection: >80% from 1150–1600 nm
UV Cold Mirror
A cold-mirror configuration that reflects a UV / short-wavelength region while transmitting longer wavelengths.
- Average transmission: >90% from 550–1200 nm
- Average reflection: >95% from 350–450 nm
Standard 45° AOI Cold Mirror
A visible-reflecting, NIR-transmitting cold mirror designed around a 45° angle of incidence.
- Average transmission: >85% from 800–1200 nm
- Average reflection: >95% from 425–650 nm
Standard 0° AOI Cold Mirror
A corresponding cold-mirror design specified for 0° angle of incidence.
- Average transmission: >85% from 800–1200 nm
- Average reflection: >95% from 425–650 nm
Compare Hot & Cold Mirrors by Optical Requirement
| Optical Requirement | Filter Direction | Recommended Configuration |
|---|---|---|
| Transmit visible light and reflect NIR to about 950 nm | Hot Mirror | 950 Economy Hot Mirror |
| Transmit visible light and extend NIR reflection to about 1150 nm | Hot Mirror | 1150 Hot Mirror |
| Extend NIR reflection toward 1600 nm | Hot Mirror | 1600 Extended Hot Mirror |
| Reflect 350–450 nm while transmitting longer wavelengths | Cold Mirror | UV Cold Mirror |
| Reflect visible light and transmit NIR at 45° AOI | Cold Mirror | Standard 45° AOI Cold Mirror |
| Reflect visible light and transmit NIR at normal incidence | Cold Mirror | Standard 0° AOI Cold Mirror |
The filter should be selected according to the required transmitted spectral region, reflected spectral region and angle of incidence.
Unsure Which IR Control Filter to Choose?
Start by defining:
- Which wavelength range must be transmitted
- Which wavelength range must be reflected
- Required visible-light transmission
- Required IR or UV rejection
- Angle of incidence
- Required filter format or mounting method
Standard hot-mirror, cold-mirror, shortpass and longpass configurations can then be reviewed against the required spectral response.
Contact UsFrom Spectral Selection to Finished IR Control Filters
After the spectral configuration is selected, the optical and mechanical format can be matched to the finished application.
- Commercial & Precision Grades — Hot mirrors and cold mirrors are available in commercial-grade and precision-grade configurations for applications ranging from industrial systems to photonics.
- Optical Surface Quality — Precision filter configurations are available with 40/20 scratch-dig surface quality and double-side polished glass for improved parallelism and optical flatness.
- Filter Mounting Options — Mounting options are available where the finished optical assembly requires a defined mechanical interface.
- Standard & Application-Specific Configurations — Standard filter options are readily available, while additional hot-mirror, cold-mirror and short-wave / long-wave pass designs can be selected according to the required spectral region.
Frequently Asked Questions
A hot mirror transmits visible light while reflecting near-infrared energy.
A cold mirror does the opposite: it reflects visible light while transmitting a specified infrared range.
The SP700 is a shortpass hot-mirror example with a cut-on wavelength of 400 nm and a cut-off wavelength of 700 nm.
It is designed to block both infrared and ultraviolet energy while transmitting the visible spectral region.
The LP715 is a longpass cold-mirror filter with a 715 nm cut-on wavelength.
It blocks visible light while transmitting NIR energy out to approximately 1100 nm and is used in vision systems where improved infrared contrast and resolution are required.
The source specifies 40/20 scratch-dig surface quality together with double-side polished glass for parallelism and optical flatness.
The published feature range for these filter products extends from approximately 350 nm to 1500 nm. Individual configurations can be selected according to the specific transmitted and reflected regions required by the optical system.
Request a Custom IR Control Filter
Need a hot mirror, cold mirror or application-specific IR control filter?
Send the transmitted wavelength range, reflected wavelength range, angle of incidence and filter format for review.