Photo sensor

In methods with light, the surface to be examined may be irradiated uniformly, a photo-sensor being used to measure its distribution alternatively, a laser may scan the surface in regular patterns, a sensor noting any differences in the amounts of light collected. 

Table I provides a schematic comparison between photo-sensor, laser, and ultrasonic methods, the different sensor systems being considered in more detail below.

Table III is a summary presentation of the CCD image sensor products of various companies in Japan, while Figure 8 shows the change in numbers of elements for photo-electric transducers. In the background of this change there was a great improvement in the clarity of pictures in home video systems (the photo-sensor for surface recognition of course was not developed exclusively for these measurements but was adapted from the general type).

Information gathered by the two-dimensional photo-sensor is essentially that of the distribution of visible light (the image). However, such images may embrace a variety of types, including ... 

Light is indispensable for life. Green plants and some bacteria use solar energy for the energy source in their photosynthesis [1-3]. Archeal bacteriorhodopsin is a membrane bound protein and works as a light-driven proton pump [4, 5]. Another role of light is information carrier that is recognized in vision and photo-sensors. 

Our retina has red, green, and blue cones which include rhodopsins as photoreceptors [6-8], Phytochromes are photo-sensors of green plants [9], Biological luminescences from fireflies [10] and some jellyfishes [11] are also beautiful activities of living organism. Recently, fluorescent proteins are routinely applied as molecular markers for gene expression in the field of molecular biology [12]. 

Second, in addition to the above, the fact that many expanded porphyrins are highly colored makes their use as dyes an obvious possibihty. Here their planar nature makes them particularly attractive as chromophores for use in liquid crystals and optical data storage applications. Also, these properties could make them of interest as photo-sensors in various clinical or pseudo-clinical situations. For instance, the high affinity by certain sapphyrins for enveloped viruses and cholesterol rich liposomes suggests that expanded porphyrins could be used to detect and/or destroy a variety of unwanted biological targets, including arterial sclerotic plaque. 

Fig. 11.8 (a) Topside view and schematic cross-sectional view of the TFT photosensor, (b) TFT photosensor images of ohgonucleotide array. Ohgonucleotides immobilized on TFT photo sensor were reacted with biotin-labeled ALDH2 1 (21 mer), and subsequently reacted with Alexa Fluor 350-labeled SA. Spot diameter 500-600 pm... 

Although the task of photovoltaic cells is to generate energy, a subclass of these devices is designed simply to detect light is photo-sensors. In this case, the conductivity requirement on the transparent conductor is lower. Hence, in addition to its electronic function as hole injector, PITX)T can be used in place of the transparent ITO electrode [172]. In this case, a highly conducting formulation of PEIX)T PSS or in situ PEDOT is used [113, 115]. 

Fig. 44. The modified metering flask of a piogram-controlled peptide synthesizer for the direct preparation of N-protected amino acid anhydrides with phosgene. (A) Solutions of N-protected amino acid salts in dichloromethane or tetrahydrofurane (B) Solution of phosgene in tetrahydrofurane (C) Dry air inlet for stirring (D) Vacuum jacket (E) Drain valve (V) Vent line. Photo sensor levels to meter (2) The solution of N-protected amino add salts (1) The addition of the phosgene solution (3) The draining of the reaction flask...

Fig. 58. The metering of liquids in different peptide synthesizers, (a) Fill line from the reservoir (b) Reflux to the reservoir after filling (c) Delivery line into the reactor (d) Metering level photo sensor (e) Variable volume by an adjustable plug (f) Solenoid valve (g) Check valve (v) Vent line...

Since a visible light image can be reproduced by the combination of three primary lights (i.e., blue, green, red), color films and papers are composed of a layered photo-sensor, which is... 

Recently, digital still cameras with solid state devices (i.e., CCD and CMOS) as photo-sensors have achieved such sensitivity and image quality as to meet the demand of most consumers and overwhelmed color films owing to their convenience. Other photographic films have been similarly overwhelmed by electronic imaging technologies. 

Fig. IS (a, b) Use of a special cuff with photo sensors for PIT measurement...

The output of the axial photo sensor was fed to the UV amplifier, the output of the photo sensor normal to the cell axis was connected to the fluorescence amplifier and the two stainless-steel discs were connected to the conductivity measuring electronic system. A block diagram of the electronic system is shown in Figure 5. 

A. Milionis, R. Giannuzzi, I.S. Bayer, E.L. Papadopoulou, R. Ruffilli, M. Manca and A. Athanassiou. Self-cleaning organic/inorganic photo-sensors. ACS Appl. Mater. Interfaces, 5, 1036-1043 (2013). 

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