Dichroic filters

Someone has materials for Dichroic filters for optical filtering.
How to electronically control the pH to various a range of absorption spectra for ions in filtering?

thank you
djalli

I didn't understand your question. you want to change pH to change absorption spectra(visible ?) of ions ? what kind of ions (organic?)? what it has to do with optical filters?

The dichroic filters are used in colour enlargers in photography for printing positives from negatives. The filters are available in yellow, magenta and cyan (secondary colors).

Bluechem ions exist in organic or inorganic. Dichronic filters are now inorganic. pH ion control has importance.

True ramesh they are used in photography but they are used in optical communication. communicating with magenta, cyan, yellow, green light etc.

375nm deep bue light is called 1A to 87C.

I want more information, that is all. I am doing some reseach for a project I have in school.

I havn't heard about dichroic filters that their color changes with pH. is it in research phase or commercially available? there are organic compounds that their color changes with pH (inorganic salts usually do not change color with pH)
but I doubt that they can be used in filter making.

dichronic filter are made of thin layers of dielectric on a substrate. they do not absorb light, but only transmit or reflect. the do that with a principle of interference.
dichronic means that they had two colors :) so if it bandpass for green, they reflect red and blue-violet :) that's why they are soo called :) no PH stuff or similar. it it were soo, this one who pattented that will become second bill gates :)

Mazi3 there is no patent (actually possibly will never be one) and there are people are working to get it done, they will possibly do it but it would be much harder the "bill gates" portion of it.

The patent may never be available. Look at liquid crystal screens. All patented by some some professor in Princeton NJ, USA and RCA Corp, none produced in USA because Japanese industry blocked RCA producing such screens in a morbid cheaper price sale on market.