Light Sensors: Color to Frequency

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The discussion centers on the quest for a light sensor that can output a frequency similar to the light it detects. Participants clarify that colors correspond to specific frequencies, referencing the VIBGYOR spectrum. They suggest that typical light discrimination is achieved using filters on photodiodes, and mention that LEDs can serve as frequency-selective sensors. The complexity arises from the diverse frequencies present in light, making it challenging to create a sensor that directly outputs a corresponding frequency. The conversation emphasizes the need for clearer specifications from the original poster to provide more targeted assistance.
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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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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.
 
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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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 ?
 
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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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/
 
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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?"
 
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Guessing won't help here. Until the OP returns with some clear answers we are just wasting our time.
 
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