Detector / Filter Combination

  1. What is the C.I.E. curve?
  2. How does PIN-10AP relate to C.I.E. curve?
  3. How accurate is the PIN-10AP response compared to the human eye?
  4. Does OSI Optoelectronics provide any calibration services?
  5. What is optical calibration?
  6. Are all standard photodiodes individually optically calibrated before shipment?
  7. Can the devices be individually calibrated?
  8. How long does the calibration add to the normal delivery of the parts?
  9. What are the different types of optical calibration that OSI Optoelectronics provide?
  10. What do I exactly receive for calibration services?
  11. Are the calibrations NIST traceable?
  12. What other types of filters are available in combination with a detector?
  13. Can OSI Optoelectronics provide photodiodes with anti-reflective coating on the glass?


1. What is the C.I.E. curve?
The human eye senses both brightness and color and its response vary as a function of the wavelength. A color model based on human perception developed by the Commission Internationale de l'Eclairage, (the International Commission on Illumination) committee.

2. How does PIN-10AP relate to C.I.E. curve?
PIN-10AP is a detector / filter combination with a spectral response matching the CIE photopic spectrum. This detector is designed to have a spectral response like that of the human eye's visual response in the photopic region. This is the response of the eye with impinging intensities greater than about 0.1 Lux. In this region the eye response peaks at 555nm.

3. How accurate is the PIN-10AP response compared to the human eye?
OSI Optoelectronics' proprietary designed AP filters are used in conjunction with a photodiode, accurately match the C.I.E. curve to within +/- 2% of area, as shown in the standard photodetector catalog.

4. Does OSI Optoelectronics provide any calibration services?
Yes, optical calibration and also position linearity calibration for position sensing detectors.

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5. What is optical calibration?
It is the measurement of the response of a photodiode at various wavelengths. It is defined as responsivity vs. wavelength. Responsivity is measured in Amps / Watts except for PIN-10AP (C.I.E. human eye response), which can also be calibrated at color temperature of 2856 ºK (CIE standard Illuminant A) in both Amps/ Lux and the equivalent Amps / Foot-candle. If you have a specific requirements please contact one of our Applications Engineers.

6. Are all standard photodiodes individually optically calibrated before shipment?
No they are not. That procedure would delay the delivery of orders in an unacceptable way and would increase the cost to the customer. Responsivity of OSI Optoelectronics photodiodes is repeatable with high accuracy.

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7. Can the devices be individually calibrated?
Yes, any of the devices can individually be calibrated if requested.

8. How long does the calibration add to the normal delivery of the parts??
About 1-2 additional weeks.

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9. What are the different types of optical calibration that OSI Optoelectronics provide?
Any photodiode (with or without optical filters) can be calibrated in house for responsivity from 400-1100 nm, 200-400 nm or combination of both (200-1100nm) in 10 nm steps. They can also be calibrated at a single wavelength. Contact one our inside representatives for pricing.

10. What do I exactly receive for calibration services?
A table and a graph consisting of wavelengths versus responsivity, and a certification.

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11. Are the calibrations NIST traceable?
All optical calibrations performed by OSI Optoelectronics are NIST traceable and will be provided with a certification of compliance.

12. What other types of filters are available in combination with a detector?
Various optical filters are available to meet specific application spectral requirements. Here are a few examples of the optical filter types available:

Shortpass filters (cut-off) transmit short wavelengths photons while blocking the longer wavelengths.

Longpass filters (cut-on) transmit long wavelength photons while blocking the shorter wavelengths.

Bandpass filters, combine a shortpass and a longpass filter property to transmit only a bandwidth of wavelengths.

Natural density filters attenuate light so that only a percentage of photons are transmitted.

Custom thin film coatings can be applied to either or both surface(s) of the filter glass to fine-tune the more stringent requirements if necessary.

13. Can OSI Optoelectronics provide photodiodes with anti-reflective coating on the glass?
Yes, anti-reflective coatings can be applied to either one or both sides of the glass to reduce glass reflection for a certain wavelength.

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