HM-690 Visible-pass / infrared-attenuating filter

HM-690 is a visible-pass / infrared-attenuating filter. The main high-transmission region is approximately 414-676 nm.

Measured wavelength range: 300-1200 nm
Lower 50% edge: ≈ 407.2 nm
Upper 50% edge: ≈ 688.3 nm
Peak transmission: ≈ 96% at 588 nm
Transmission ≥80%: 414-676 nm; 942-957 nm; 1044-1079 nm
Custom options: Wavelength response, dimensions and operating conditions

Values shown are sample measurements. Final specifications are agreed for your order.

Visible-pass / infrared-attenuating filter (HM-690)

HM-690 is a visible-pass / infrared-attenuating filter. The main high-transmission region is approximately 414-676 nm. It can be considered when visible light is required and part of the longer-wavelength spectrum needs attenuation.

Optical performance

Measured wavelength range: 300-1200 nm. Performance outside this measured interval is not established by this curve.
Selected regions at or above 80% transmission: 414-676 nm; 942-957 nm; 1044-1079 nm. Approximate measured intervals.
Selected regions at or below 5% transmission: 300-395 nm; 728-896 nm. Measured sample intervals; confirm the required blocking for your order.
Peak transmission: Approximately 96% at 588 nm. Peak wavelength is not the same as a defined centre wavelength.
Average measured transmission, 300-380 nm: 0.381%. Calculated from the factory sample data.
Average measured transmission, 450-670 nm: 94.316%. Calculated from the factory sample data.
Average measured transmission, 710-850 nm: 2.442%. Calculated from the factory sample data.
Measured edge at 50% transmission: Approximately 407.2 nm. Interpolated absolute-transmission crossing, checked against the factory summary.
Measured edge at 50% transmission: Approximately 688.3 nm. Interpolated absolute-transmission crossing, checked against the factory summary.
Customization: We can customize stock and sample-book designs. Tell us the wavelength response, size and operating conditions you need.

These values come from the measured samples and help you choose a starting design. We will agree the final specification for your order. Custom versions have their own specifications and measured curves.

Applications to consider

Visible-light camera systems: Evaluate attenuation of unwanted longer-wavelength light while retaining the visible signal. Check the entire detector sensitivity range, including any transmission recovery.
Illumination optics: Consider spectral conditioning between a source and the illuminated object. Confirm the source-weighted transmitted power and how reflected or absorbed power is managed.
Color-imaging development: Compare the visible response with the required camera color balance. Account for differences at the blue and red edges before choosing the optic.

Choosing this filter

Additional regions reach at least 50% transmission at approximately 933-975 nm; 1020-1109 nm; 1187-1200 nm. Include these in the detector and blocking assessment.
Check the full wavelength range of your light source, the wavelengths your detector responds to, and how much unwanted light you need to block. Use the full curve when choosing a filter; the product code and peak do not tell the whole story.
Tell us the angle at which light reaches the filter and whether the beam is parallel or converging. For demanding rejection or high-power use, confirm the required blocking and power-handling specifications.

Custom options

Start with this stock or sample-book design, then tell us what you need to change. We can discuss the wavelength bands, transmission, blocking, angle, glass material, size and operating conditions with you, and agree a specification for your custom filter.

Transmission spectrum

Questions about HM-690

Where does HM-690 transmit at least 80% in the measured curve?

The measured regions at or above 80% transmission are 414-676 nm; 942-957 nm; 1044-1079 nm. They are measured intervals, not guaranteed passband tolerances. Compare the full curve with the signal wavelengths you need to retain.

Could HM-690 pass light outside its main band?

For HM-690, additional regions reach at least 50% transmission at approximately 933-975 nm; 1020-1109 nm; 1187-1200 nm. If your detector responds there, include that light in the background assessment or discuss an additional blocking requirement.

Discuss this filter with KUPO - include the product reference, source wavelength, working angle and required dimensions.