Photodetector integration

Extended Structural Integration OLED/Sensing Component/Photodetector Integration... 

From the early 1980s to present, infrared sensitive two dimensional arrays were mated to integrated circuits for signal processing and sensitivity to better than 0.03 K (see Photodetectors). These focal plane arrays of some 500 by 500 elements eliminate the need for scanning and provide good spatial resolution. Some versions have no special cooling requirements. The development trend is to increase the number of pixels to improve resolution, increase the field of view and keep the size and cost of the optics within acceptable bounds. 

Roelkens, G. et al. 2005. Integration of InP/InGaAsP photodetectors onto silicon-on-insulator waveguide circuits. Opt. Express 13 10102-10108. 

The optoelectrical characteristics of the display have been measured using an integrating sphere and a calibrated photodetector connected to a radiometer [30]. First, the total luminous flux from the AM-PLED was measured for different /data. Then, the AM-PLED luminance was calculated from the measured display luminous flux. For a Lambertian emitter, the luminance (L) can be calculated from the measured luminous flux (<1>) by using the following equation ... 

The intensity of the fluorescence emission detected at the photodetector stage was plotted as a function of temperature over the same range, and this is shown in Figure 11.22. It falls off rapidly with temperature increase over the whole temperature region. This does not contradict the experimental evidence of Burns and Nathan(56) who showed that the fluorescence quantum efficiency of the ruby fluorescence integrated over the entire band from 620 to 770 nm is independent of temperature (to 5%) in the region from-196 to 240°C, for the emission detected here is only the A-line part of the total fluorescence emission. 

FIGURE 7.7 Cross-sectional view of a microchemical chip integrated with some optical components, (a) The microchemical chip showing the microlens (entrance and exit), the 3000-A Cr aperture layers (entrance and exit), and microchannel (25 pm deep) (b) the microchemical chip together with the pinhole (800 pm) and interference filter for detection by the photodetector [688]. Reprinted with permission from the American Chemical Society. 

Figure 3.5. Engineering drawing of a solid-state photodetector with integrated amplifier, current-to-voltage converter, and temperature controller, (courtesy PerkinElmer Optoelectronics)...

Nevertheless, the first functional working TFT was demonstrated by Weimer in 1962 (Ref 2). He used thin films of polycrystalline cadmium sulfide, similar to those ones developed for photodetectors. The simplified structure is shown in Fig. 1(b). Other TFT semiconductor materials like CdSe, Te, InSb and Ge were investigated, but in the mid-1960 s the emergence of the metal oxide semiconductor field effect transistor (MOSFET) based on the crystalline silicon technology and the possibility to perform integrated circuits, led to a decline in TFT development activity by the end of the 1960s. 

When the beam or source signal is larger than the active detection area of the photodetector, an integrating sphere can be used to trap and reflect signal evenly to the sensor, as shown in Figure 4. 

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