A dual bandpass filter is a type of optical filter that allows transmission of light in two specific wavelength ranges, while blocking other wavelengths. It is designed to transmit light in a certain range of wavelengths, while blocking all other wavelengths outside of that range.

A 940nm filter, on the other hand, is a filter that is designed to transmit light only in the 940nm wavelength range. This type of filter is commonly used in applications where the detection of infrared radiation is necessary, such as in surveillance cameras, night vision systems, and medical equipment.

Coligh’s stock standard dual bandpass visible + 940nm  NIR filter:

• Type: dual bandpass filter
• Angle of incidence: 0°
• Center wavelength: visible +/-20nm, 940nm+/-10nm
• FWHM: visible@200nm & 940nm@50nm
• Thickness: 1.0mm, 1.1mm, 0.5mm, 0.7mm
• Surface quality: 80/50, 60/40
• Size: smaller than 100*100mm

Custom option:

• • 550nm+850nm, 475nm+850nm or other wavelength client request
  • Working wavelength: according to client’s request
  • Material and thickness: according to client’s request
  • Surface quality: 40/20 is in option
  • Size: Any size round or square smaller than 100*100mm