Multiplexing semiconductor

This comparison of the spectroscopic properties of the different types of fluorescent reporters underlines that semiconductor QDs and upconverting nanoparticles have no analogs in the field of organic dyes. Therefore, their unique features are unrivaled. The different molecular labels detailed here each display unique advantages that can compete with some of the favorable features of QDs and upconverting phosphors such as long lifetimes in the case of MLC systems and lanthanide chelates or very narrow emission bands for lanthanide chelates beneficial for spectral multiplexing. 

For the last decade, semiconductor diode-laser sensors have been developed at Stanford University for measurements of important parameters in laboratory-and industrial-scale gaseous flowfields. For example, a mass flux sensor was developed based on rapid measurements of O2 absorption near 760 nm in supersonic flowfields [1] and a multiplexed sensor was developed for the simultaneous measurement of various pollutants representing unburned hydrocarbons (CH4, CH3CI) near 1.65 pm [2]. 

A pn-junction layer 1 of HgCdTe, which has a passivation layer 12, is bonded to a silicon multiplexer chip 2 by a bonding layer 4. The lower layer 9 of the heterojunction I is p-type and the upper layer 10 is n-type. Holes 8 are ion-etched right through the semiconductor layer to contact pads 6. The regions of the layer 9 forming the walls of the holes are converted to n-type by the ion beam. A homojunction is thus formed in parallel with the heterojunction. The compositions are selected so that the heterojunctions determine the infrared response and noise characteristics and the homojunctions act as noiseless isolation devices. 

Heterogeneous immunoassay in which a nanometer-sized (less than lOnm) semiconductor quantum dot is used as a label. A quantum dot is a highly fluorescent nanocrystal composed of CdSe, CdS, ZnSe, InP, or InAs or a layer of ZnS or CdS on, for example, a CdSe core. Multiplexing is possible with these labels because the emission properties can be modulated by changing the size and composition of the nanocrystal (e.g., CdS emits blue light, InP emits red light). 

Roth, D. Py, C Fukutani, H. Marshall, P. Popela, M. Leong, D. (2001). An Organic Digital Integrated Multiplexing Clock Display, Presented at the 10th Canadian Semiconductor Technology Conference, Ottawa, Canada, Aug 13—17. 

HORIBA Jobin Yvon produces two Raman process analysers, the RPA-HE and the RPA-AX. They provide coverage from 150-3200 cm They both have no moving parts and use an air-cooled CCD detector. They can be conhgured with lasers at 532, 633, 785 and 830nm (only the RPA-AX). The main difference between the two systems is that the RPA-HE system can obtain multiplexed information from up to four hbre probes simultaneously while RPA-AX can be multiplexed to up to 64 separate channels of information. They are used in the semiconductor industry and for polymer characterisation and pharmaceutical manufacturing. 

Semiconductor lasers have a tremendous potential for use in optical communication systems due to their high efficiency, small size, and direct modulation capability. Because of their small size, they become the ideal source for optical radiation to be utilized in an optical fiber transmission system. The reason for developing an optical communications system is that these systems can take advantage of the large bandwidth that optics has to offer. For example, in a conventional copper wire communication system, the bandwidth of the transmission channel, i.e., the coaxial cable, is limited to approximately 300 MHz. In a normal telephone conversation, fi equency components up to 3 kHz are required for the listener to understand the conversation. By multiplexing many telephone conversations on different carrier fi equencies, approximately 100,000 conversations can be sent through a single... 

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