CCS/OPT8241: OPT8241

1) The light source bandwidth is between 10M and 200MHz, which determine the modulation frequency 5MHz to 90MHz. Are these limited by the current OPT8241 sensor configuration or we can go beyond this range?

>> 5MHz - 90MHz are sensor limits.

2) In the design parameters(outputs), the ratio between the Illum Average Optical output power and Illum Peak Optical output power represents the light source duty cycle, correct?

>> Peak power is instantaneous (Pulsed) power when illumination is ON.  Average power is pulsed power averaged over time.

 For instance, if Average is 180mW, Peak is 1W, the duty cycle of illumination should be 18%, if the modulation frequency is 50MHz ( t=20ns), the time of illuminator turning on should be 3.6ns (20x 18%=3.6).

 Is there is minimum duty cycle requirement for the OPT8241?

>> Illumination is only pulsing during integration time.  Duty cycle of light pulses during integration time should be 50% ON, 50% OFF.

3) There is a Biinning number of the sensor, larger Binning number lead to less optical output power requirement. What is the disadvantage of using a larger binning number? How to change the binning the number in a real system?

>> Binning means pixels are combined to form a macro-pixel.  Macro pixel collects more light (larger pixel area) and there SNR is better, so less light power is required for a given depth resolution.  Downside of binning is losing spatial resolution.

see Section 7.3.7.3 on page 34 of OPT9221 data sheet for how to setup binning.