Light Sensors: Color to Frequency

In summary: It's better to wait for more information before trying to answer the question. In summary, the conversation discusses light sensing and the possibility of a light sensor with a frequency response similar to the source frequency. The concept of colors being related to frequency is mentioned, as well as the use of filters and LEDs as light sensors. The use of OLEDs and interferometers for measuring light frequency is also suggested. However, it is noted that converting light to frequency may be difficult due to the nature of light as an electromagnetic wave.
  • #1
alejandro ureta
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Hi all, I‘m a recent member in this forum, very glad I found it. I am interested in light sensing and would like to know if there is any sort of light sensor whose response is manifested and measurable as an emmisson frequency similar to the frequency which is receiving or sensing. I am particularly thinking in a light-to-frequency alike sensor whose frequency response is directly linked and of similar frequency to the source frequency. thanks.
 
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  • #2
Well yes, Colours are related to their frequency. VIBGYOR, heard about this? This is the order of the seven colours of our rainbow in order of their frequency. V-Violet, I-Indigo, B-Blue, G-Green, Y-Yellow, O-Orange, R-Red. In this Red color's frequency< Orange color's frequency< Yellow color's frequency and vice versa till Violet.
 
  • #4
alejandro ureta said:
I am particularly thinking in a light-to-frequency alike sensor whose frequency response is directly linked and of similar frequency to the source frequency. thanks.

I'm not quite sure what you're asking for in that sentence

Oftentimes color discrimination is done with filters over ordinary photodiodes

http://www.pixelteq.com/product/pixelsensor/?gclid=CN-mv8nvgcUCFZKGaQodWj0A-Q LED's can be used as light sensors and they're naturally 'frequency' selective...

see if this article has any clues for you
http://makezine.com/projects/make-36-boards/how-to-use-leds-to-detect-light/

led-2.jpg


Figure A shows the spectral response of 7 blue, green, red, and near-infrared LEDs that replace the usual silicon photodiodes and filters in my modified Multi-Filter Rotating Shadowband Radiometer, used for solar spectroscopy.
old jim
 
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  • #6
Welcome to PF.
The problem here is that light is usually made up of very many different colours all with different intensities.

Why do you need the sensor ?
Can you give an example of the output you want ?
 
  • #7
OLED's ? fascinating. My 1962 Chrysler had an electroluminescent dashboard...perhaps precursors to OLED's.

get-attachment.asp?action=view&attachmentid=40895.jpg

Thanks dlgoff , for introducing me to yet another world all its own..
 
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  • #8
The most straightforward way to measure light frequency is an interferometer.

AN analogy would be to shine the light through a prism which refracts based on frequency, and measure physically where the output is positioned with a calibrated ccd or camera.

Your request that the sensor have a frequency output similar to the light frequency is pretty tough. Since light is an EM wave, what form would you propose the sensor output take?https://www.physicsforums.com/threads/how-do-we-measure-the-frequency-of-light.442887/
 
  • #10
but a spectrometer does not do what he asked for. It certainly measures spectral frequency (using diffraction or interference techniques) but it does not convert light as he suggests.

He requests a "light-to-frequency alike sensor whose frequency response is directly linked and of similar frequency to the source frequency"

To which I ask "Since light is an EM wave, what form would you propose the sensor output take?"
 
  • #11
Guessing won't help here. Until the OP returns with some clear answers we are just wasting our time.
 
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FAQ: Light Sensors: Color to Frequency

1. What is a light sensor?

A light sensor, also known as a photosensor, is a device that detects and measures light levels in its surroundings. It converts light energy into an electrical signal, which can then be used to trigger other electronic devices or systems.

2. What is the principle behind color to frequency conversion in light sensors?

The principle behind color to frequency conversion in light sensors is based on the fact that different colors of light have different frequencies. Light sensors use a filter or a set of filters to selectively allow certain frequencies of light to pass through, and the resulting output is a frequency that corresponds to the color of the light being detected.

3. How accurate are light sensors in measuring color?

The accuracy of light sensors in measuring color depends on the specific sensor and its design. Generally, light sensors can accurately detect and measure colors within a specific range or spectrum. However, they may not be as accurate in detecting subtle differences in shades and hues.

4. What are some common applications of light sensors that use color to frequency conversion?

Light sensors that use color to frequency conversion have a wide range of applications, including color detection in industrial settings, color sensing in automatic lighting systems, color sorting in food processing, and colorimetry in scientific research and analysis.

5. Are there any limitations to using light sensors for color to frequency conversion?

One limitation of using light sensors for color to frequency conversion is that they are susceptible to interference from ambient light. This can affect the accuracy of the frequency output and may require additional calibration or filtering to compensate. Additionally, light sensors may not be able to detect colors outside of their designated range or may have difficulty distinguishing between very similar shades or hues.

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