Excimer lamp

Excimer lamps are quasi-monochromatic light sources available in UV wavelengths. The light is produced by silent electrical discharge through gas in the gap between two concentric quartz tubes. Electronically activated molecules are produced in the gas phase and decompose within nanoseconds to produce photons of high selectivity. This process is similar to the process in excimer lasers. [Pg.26]

The most important difference between excimer and standard UV lamps is that the former are incoherent radiation sources and can therefore be used for large area applications. Different wavelengths can be produced by choosing different gas fills in the gap between the quartz tubes. [Pg.26]

Stimulated (laser) excimer emission can be generated in pulsed high-pressure glow discharges. Dielectric barrier (silent) discharges or micro-wave discharges can be used to produce quasi-stationary or continuous incoherent excimer radiation. [Pg.26]

With the narrow range of wavelength of the excimer lamp, a specific initiator can be selected with the maximum efficiency in that range. Thus, it is possible to reduce the amount of photoinitiator from that used for conventional UV sources and reduce the cost of the material and amounts of unreacted initiator in the finished coated substrate. Excimer lamps can be used for both free radical and cationic photoinitiators. [Pg.26]

Currently, there are two types of commercial excimer lamps barrier-discharge- and microwave-driven lamps. [Pg.26]

Excimer lamp Excimer laser Excipients Excitation spectrum Exclamation Exclusion chart Exelderm Exelgyn... [Pg.387]

Excimer lamps have opened the possibiHty of cost-effective large-area direct photochemical vapor deposition (PCVD). PCVD of stoichiometric, insulating Si02 onto Si wafer has been reported using SiH and N2O as gas-phase precursors and the 172-nm radiation from a Xe 2 lamp (54). Deposition... [Pg.391]

Exchanger design equation, 13 195 Exchange repulsion, 23 93 Excimer lamp technology, 19 107-108 Excimer lasers, 14 691-693 17 372 19 115 applications of, 14 693 species of, 14 692t... [Pg.339]

Figure 22. Human embryonic kidney cells (A), rat vascular smooth muscle cells (B, C) and human osteoblast-like MG 63 cells (D) in cultures on micropattemed surfaces. A, B PTFE irradiated with UV light produced by a Xe2 -excimer lamp for 30 min in an ammonia atmosphere through a mask with holes 100 pm in diameter and center-to-center distance 300 pm C PE irradiated with Ar ions (energy 150 keV, ion dose lO ions/cm ) through a mask with holes 100 pm in diameter and center-to-center distance 200 pm fullerenes Qo deposited through a mask with rectangular holes with an average size of 128 3 pm per 98 8 pm on glass coverslips. Day 7 after seeding. A native cells in an inverted phase-contrast microscope B, C cells stained with hematoxylin and eosin, Olympus microscope IX 50 D cells stained with fluorescence-based LIVE/DEAD viability/cytotoxicity kit (Invitrogen), Olympus microscope IX 50. Bars 300 pm (A), 200 pm (B, D), Imm (C) [10,11].

Excimer lamps, a relatively recent new development, represent a new class of monochromatic UV sources. Excimers (excited dimers, trimers) are weakly bound excited states of molecules that do not possess a stable molecular state. ... [Pg.9]

Excimer lamp Dielectric barrier (silent) discharge 172,222, 308 1-10 UV curing. Major R D... [Pg.12]

Mercury lamps (low, medium, and high pressure) Elecfrodeless (microwave-powered) lamps Excimer lamps... [Pg.22]

The excimer lamp of this type is made by Heraeus Noblelight (Hanau, Germany) and consists of two concentric cylindrical quartz tubes, fused together on both ends. The excimer gas mixture is filled in the gap between the two tubes and sealed. The electrodes are placed outside the discharge... [Pg.26]

Barrier discharge excimer lamp. (Courtesy of Heraeus Noblelight.)... [Pg.27]

In addition to the low surface femperature, excimer lamps have fhe advantage that they start immediately, so they can be switched on and off as needed. There is no need for sfandby function and for a shuffer system, so no movable parts are necessary on the radiation head. Both continuous and pulse mode operation is possible. The lamps are very compact, which is particularly important for the printing industry, because it is possible to retrofit them into the existing process. [Pg.27]

Fusion Systems (Gaithersburg, MD) at one time offered 240 W/cm microwave-driven excimer lamps within its VIP (Versatile Irradiance Platform) series. They were among the most powerful sources of UV radiant power,i available... [Pg.28]

Anofher developmenf is free radical polymerization of neaf acrylafes wifhouf phofoinifiafor using 172 and 222 nm excimer lamps. Photons emitted from fhese radiafion sources are absorbed by many acrylafes generafing free radicals direcfly. ... [Pg.78]

Ushio America, Inc. www.ushiosemi.com UV equipment, UV light sources, UV excimer lamps... [Pg.264]

Monochromatic UV radiation is emitted by excimer lamps, in which microwave discharge5 or a radio-frequency-driven silent discharge6 generates excimer-excited states of noble gas halide molecules, which decay by the emission of monochromatic UV radiation. In the ground state, the excimer molecules decay into atoms. Therefore, no self-absorption of the UV radiation can occur. All photons are coupled out of the discharge.4... [Pg.23]

FIGURE 3.3 The barrier-discharge-driven excimer lamp (courtesy of Heraeus Noblelight). [Pg.36]

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