Patent ID: 9184698
Filing Date: 2015-11-10
Classification: G02C,H03B,H03L

Abstract:
1. A system comprising: an adjustable oscillator configured to generate a periodically varying output signal at an oscillator frequency, wherein the oscillator frequency is at least partially based on an input control signal; a light-sensitive element configured to generate an output signal indicative of an intensity of light incident on the light-sensitive element; a controller configured to: (i) receive a first input signal based on the output signal from the light-sensitive element, wherein the first input signal has a frequency based on a reference frequency at which an intensity of light incident on the light-sensitive element periodically varies; (ii) generate a control signal based in part on the reference frequency; and (iii) provide the generated control signal to the adjustable oscillator to thereby adjust the oscillator frequency; and a pulse generation circuit configured to generate the first input signal received by the controller, wherein the pulse generation circuit comprises a comparator configured to: (i) receive a voltage signal based on the output signal from the light-sensitive element; and (ii) output a series of voltage pulses, wherein each voltage pulse corresponds to the received voltage signal exceeding a threshold voltage.