Three Transducers Embedded into a Single SiC Photodetector: LSP Direct Image Sensor, Optical Amplifier and Demux

A double pi’n/pin a-SiC:H heterostructure with two optical connections for light triggering in different spectral regions is presented and its behavior as image and color sensor, optical amplifier and demux device is discussed. The design and the light source properties are correlated with the sensor output characteristics. Different readout techniques are used. When a low power monochromatic scanner readout is used the transducer recognizes a color pattern projected on it acting as a color and image sensor. Scan speeds up to 104 lines per second are achieved without degradation in the resolution. If the photocurrent generated by different monochromatic pulsed channels is readout directly, the information is demultiplexed. Results show that it is possible to decode the information from three simultaneous color channels at bit rates per channel higher than 4000 bps. Finally, when triggered by an appropriated wavelength, it can amplify or suppress the generated photocurrent working as an optical amplifier. Electrical models are present to support the sensing methodologies.