Photodiode Definition and 72 Threads

How can I convert the voltge measured across a photodiode to light output or intensity or any other photonic unit? I am trying to measure the light intensity/output of some LEDs using a photodiode but the photodiode measures voltage as a function of light intensity.

I am using a BPW21R photodiode to measure irradiance instead of a BPW21 photodiode in a pyranometer circuit that could be found in the pdf link below. How should I calculate irradiance(W/m^2) from the current produced in a transimpedance amp circuit if there is no Spectral...

What does the bandwiidth of a photodiode signify? I just know that it is related to speed of photodiode, but while dealing with PD practically in lab. , what does its bandwidth tell me ?

I am curious how does the wavelength of light let's say 800nm/s collected by a photodiode results from the saturation of the plate 1mm. sq. I have this photodiode from a cdrom and it has 6 legs, two do not have a bias-junction, the other four do, and the collector is slightly greenish. I...

Hi I'm pretty new to the forums. I've been searching and can't find anything on this. Can anyone show me how to calculate the current/voltage produced by a photodiode?

Hi I am new to this forum but have been interested in reading many threads and would like to know if any of the experts could help. I am looking to make a circuit that I can measure different output levels of a photodiode from the amount of "signal" reflected onto it from a particular...

Homework Statement Okay so I've got a photodiode with reverse current linear dependence of 0.3uA/Lux and dark current of 20nA. I need to design a circuit (4-20mA current transmission system) with 4mA at zero light intensity and 20mA at 4x10^4 Lux. The Attempt at a Solution Struggling! I...

Hi guys! I'm a beginning EE students, and haven't taken many courses yet (haven't even covered transistors in my circuits class yet-- we're up to diodes, woo!). For a "for fun" project, I've been messing around with the Arduino microcontroller...

Like the title states, is the voltage produced by a photodiode, or any PV device for that matter, dependent upon that devices temperature? To rephrase, if you have a fixed amount of photons coming in contact with the business end of a photodiode, is the voltage or current generated by the...

Hi everyone, I'm new to the forum and basically need help to build a little gadget to measure the intensity of light that passes through a tube filled with solutions of different dye concentrations. I have a 10530DAL photodiode, and a light source. What I'm doing now is measuring the...

Hi! I'm having trouble figuring out the difference between a pixel and a photodiode as well as a capacitor- they all seem like the same property to me! :confused: Can someone please help me?:confused: Thanx

Pixel + Photodiode!help Hi! I don't know if this is the right place for this topic but I could not find "Digital Technology" elsewhere so here I go: I'm having trouble figuring out the difference between a pixel and a photodiode as well as a capacitor- they all seem like the same property...

Hihi, http://sales.hamamatsu.com/assets/applications/SSD/si_pd_circuit_kspd1043e06.pdf 5. high-sensor From the message there, I don't understand what is the meaning of time constant of resistor? Why does it say that the time response of the circuit depends on the time constant...

Hi, I have a photodiode circuit (attached), where a photodiode is hooked up to a current to voltage opamp connected to a voltage divider. This circuit works as intended: when there is light, Vo ~ 3.3V, and when there is no light, Vo ~ 0.3V. However, when I measured the rise time of this...

Hi frnds, I have the photodiode DET10A and I am trying to take its output to computer using USB-6008. Labview feels that the DAQ’s ports are open and shows values 1.4 – 1.42. However, when I connect the photodiode to a multimeter or oscilloscope I see correct signal. the maximum photodiode...

Just thought i would ask, when a photodiode is acting in reverse bias, it allows current to pass but does not generate voltage. In fact, it has a voltage drop. When in forward bias, it allows current to pass but also generates an EMF. Is this correct, any response would be appreciated.

I don't really have much knowledge of electronics and kindly seek your helps. The + sign above the photodiode, what does it mean? Does it mean I have to connect the cathode to the ground?? Then, about the direction of the current, why does the current flow from cathode to anode? I...

Hey guys, just another question regarding photonics. From looking at an I - V characteristic of a typical photodiode: http://www.rp-photonics.com/img/photodiode.png I don't understand what it means by there being a negative voltage and a negative current. I suspect the negative in the current...

HI all, i'm currently working with IR sensor diodes, and trying to find a proper device for my project, however i haven't found a good unit which fills my needs. Now that i have extended my search to phototransistors, i wonder are they compatible with photodiodes? Im using Atmel's...

Homework Statement I am trying to finish the equation, to compare it against a set of data so I can then find the accuracy of my results in relation to the equation: I(dark) = I(sat) * e(qV/kT) -1 I have the following data: Va - the applied (bias) voltage q kB - Boltzmann Constant...

whats the characteristics of a photodiode? what will its resistance be, if there is a high intensity of IR radiation falling on it, and what will its resistance be, if there is a low intensity of IR radiation falling on it?

Hello, I am having a bit of trouble with the following problem: Assuming a built in voltage equal to the bandgap voltage, calculate the slowest possible transmit time for a carrier with 5V reverse bias applied to the GaAs photodiode. I would be able to do this problem without difficulty if...