Infrared window

Gentilman, R. L., Bibenedetto, B., Tustison, R., and Pappis, J., Chemical Vapor Deposition of Ceramics for Infrared Windows, in Chemically Vapor Deposited Coatings, (H. Pierson, ed.), pp. 47-53, The Amer. Ceram. Soc., Columbus, OH 43214 (1981)... 

A. E Armington, H. Posen, and H. Lipson, Strengthening of Halides for Infrared Windows, Jour. Electronic Mater., 2,127 (1973). 

Fig. 1. Absorption coefficients of oxyhaemoglobin, deoxyhaemoglobin and water as a function of wavelength. The near-infrared window of tissue is defined as the spectral region between approximately 700 - 900 nm, where the absorption coefficients are at minimal levels...

Solvent-elimination approaches include evaporative spray deposition onto infrared-transparent surfaces (141) or reflective surfaces and powders (142, 143). Other approaches include partial evaporation of the mobile phase before spray deposition (144, 145), and continuous liquid-liquid extraction systems that transfer solutes from LC mobile phases to solvents possessing an infrared window (146). Spray systems include both pneumatic and ultrasonic nozzles (147). 

Approximate low-energy cutoff for common infrared windows ... 

Figure 4.4-1 Basic composition of an apparatus for matrix-isolation experiments a) Rotatable cryostat with gas-handling system, b) Sectional view in the level of the matrix support, (1) matrix support, (2) refrigerator, 4-40 K, (3) radiation shield, 77 K, (4) vacuum shroud, (5) infrared window, X KBr, y PE, z quartz glass, (6) spray-on nozzle, (7) synthetic device, e.g., Knudsen cell, (8) turbomolecular pump, p < 10 mbar, (9) to backing pump, (10) transfer line, quartz or stainless steel capillary, (11) needle valve, (12) inert gas inlet, Ne, Ar, N2,..., (13) bulb for gas mixtures, (14) capacity manometer, (15) sample, (16) to high-vacuum system.

Semiconductor devices sensitive to infrared radiation in either of the two atmospheric infrared windows can be built, in large numbers, on the surface of a chip. An infrared image focused on the surface of sudi an array can be read off electronically as image information, and this information used to construct a visible-light image on a screen. 

Fig. 9 Structure and infrared absorption bands correlation chart. Transmission ranges for infrared window materials Csl, KBr, ZnSe, KRS-5, Baf2, Cap2, and NaCl are also indicated on the chart. (From Perkin-Elmer Corporation.)...

The mull technique involves thoroughly mixing the sample with a low. apor pressure, medium-molecular-weight hydrocarbon, generally known as N jiol. The mull or dispersion is then held between two infrared windows and its spectrum recorded. Since the Nujol itself absorbs radiation (absorption bands at —2900, —1460, and —1375 cm )> the observed spectrum consists of the superposition of the spectrum of the compound of interest on that... 

Aluminate glasses are transparent in the infrared region and these too have specialist applications, although the glass-forming ability is poor. Recently, rare earth aluminate glasses have been developed commercially in optical applications as alternatives to sapphire for use in, for example, infrared windows. 

D. C. Harris, Diamond the ultimate durable infrared window material. Naval Res. Rev., 3 3-16 (1992)... 

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