Cold light mirrors

Cold light mirrors have very high reflection characteristics for the visible light and a high transmission for infrared radiation. They are particularly suitable for illumination systems in which the illuminated object must be protected from thermal... 

Cold light mirror for strongly curved substrates. 

Such transparent heat mirrors have important application, for example, in combination with cold light mirrors as thermal radiation shields in projection and illumination techniques and potential applications also in solar energy collection, window insulation, etc. 

Cold light sources are used when strong illumination is needed, but drastic heat input into the object must be avoided, e.g., during microscopic observations. Usually a halogen lamp is installed with a concave mirror at the back and a system of lenses in the front. Unwanted IR and UV... 

Heat- and light-separation coatings (also known as hot and cold mirrors) are important applications that separate the hot (infrared) from the cold (visible) radiation. The principle is shown schematically inFig. 16.2. The transmittance of a cold mirror is shown in Fig. 16.3a. This mirror is coated with a dielectric film reflecting more than 90% of the... 

Our ups and our downs of behavioral output ride a wave of internal body temperature that mirrors the diurnal fluctuations of temperature that follow the sun s rising and setting. Light, of course, is symphonically orchestrated in the cosmic world of day and night and tells us even consciously what thermal time it is more clearly and crisply than hot/cold sensitivity. 

The advantage of the arc lamp is that the actual light source is very small. It is concentrated between the electrodes in a volume of a few mm3, and the outgoing beam can be focussed accurately by optical devices such as lenses and curved mirrors. However, the power supplies needed for arc lamps are much more complex and expensive than those for incandescent lamps. Arc lamps are not electrically conducting when cold, so that a high voltage pulse is required to start them. The current must be controlled very accurately to ensure a steady light intensity. 

The solution containing the arsenic compound is then added in small amounts at a time to the contents of the flask. If much arsenic is present, there will be an almost immediate blackening of the silver nitrate solution. Disconnect the rubber tube at C. Heat the tube at A to just below the softening point a mirror of arsenic is deposited in the cooler, less constricted portion of the tube. A second flame may be applied at B to ensure complete decomposition (arsine is extremely poisonous). When a satisfactory mirror has been obtained, remove the flames at A and B and apply a light at C. Hold a cold porcelain dish in the flame, and test the solubility of the black or brownish deposit in sodium hypochlorite solution. 

Fig. 9.4 Time evolution of PEC water splitting on a Ir02/Ta0N electrode under visible light (of wavelength longer than 420 nm) illumination using a 300 W Xe lamp (Cermax equipped with a cold mirror CM2, a cut-oflf filter Hoya L42) at 0.8 V versus Pt in an aqueous 0.1 M Na2S04 electrolyte at 288 K. Stoichiometric H2 02 (2 1) gas production was observed. Adapted from Ref. [10]...

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