Timeline for Amplifying a small signal from a phototransistor
Current License: CC BY-SA 4.0
6 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Aug 20, 2021 at 17:23 | comment | added | Ahmad Al-Baghdadi | The coupling between them is great, the light coming out is barely visible because the light goes through a liquid sample where most of it get absorbed and I read the remaining passing light. I will try a lens if the amplifier doesn't cut it. Thanks! | |
| Aug 20, 2021 at 10:24 | comment | added | bobflux | Can you get a better coupling between the output of the fiber and the phototransistor, or use a lens at the other end to focus more light into the fiber? | |
| Aug 19, 2021 at 16:18 | comment | added | Ahmad Al-Baghdadi | The light comes from a fiber optic cable with a 1mm diameter, so I can't put them in parallel. I though about using lenses but I prefer an electronics-based solution than a mechanical one, as I would need to worry about the focal length and the lens diameter. | |
| Aug 19, 2021 at 14:44 | comment | added | bobflux | If the light to be measured comes from a source that is always in the same place, have you considered using a lens to focus more light on the phototransistor? You could also use more phototransistors in parallel to average out the noise. | |
| Aug 19, 2021 at 6:52 | comment | added | Ahmad Al-Baghdadi | A transimpedance amplifier is a great idea, maybe I will add it as a preamplifier then amplify the signal to the desired output using another amplifier so I can get rid of the MOhm resistors. The feedback capacitor looks promising. I will build another iteration with all the comments in mind and will post the updates. Thanks | |
| Aug 18, 2021 at 15:46 | history | answered | bobflux | CC BY-SA 4.0 |