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With the advantages of fluorescence excitation and environmental adaptability simultaneously, Ultraviolet Image Spectroscopy has shown irreplaceable features in the field of latent target detection and become a current research focus. A design of Large Aperture Ultraviolet Spatially Modulated Imaging Spectrometer (LAUV-SMIS) based on image plane interferometer and offner system was first proposed in this paper. The data processing technology of time-spatial modulation FTIS in UV band has been studied. The latent fingerprint could be recognized clearly from the image since which is capable to meet the need of latent target detection. The spectral curve of the target could distinguish the emission peak at 253.7nm and 365nm when the low pressure and high pressure mercury lamp were used as the illuminator. Accurate spectral data of the target can be collected on the short and long wave ends of the working band.

A study was conducted emission spectra germicidal low pressure mercury lamp at currents 100–306 mA located in a closed opaque cavity. It is shown that the lamps located in the cavity with perfectly reflecting and absorbing internal surfaces, in the emission resonance line of mercury is dominant at λ r = 253.65 nm. The same pattern is observed in the tube placed in a cavity with diffusely reflecting surface at a low current of about 100 mA. However the picture of spectrum changes at higher discharge current. The spectrum of the lamp with arc discharge at a current of 306 mA contains the maxima of the spectral lines. Its intensities are approximately described by Planck's radiation law at the temperature of 9270 ± 230 K. The mechanisms of establish thermal equilibrium are discussed.

With the method of ultraviolet absorption spectrum, the exact absorption cross-section with the light source of the low-pressure mercury lamp was determined, during which the optimum wavelength for mercury concentrations inversion was 253.69 nm, the highest detection limit was 0.177 μg/cm 3 , and the lowest detection limit was 0.034 μg/cm 3 . Furthermore, based on the differential optical absorption spectroscopy(DOAS), the relationship between the integral parameters (IP) and the concentration as well as the signal-noise ration (SNR) under the conditions of gas flow was determined and the lowest detection limit was figured out to be 0.03524 μg/cm 3 , providing a method of DOAS to de-noise through the comparison between the mercury concentration values produced by DOAS and that produced by the wavelet de-noising method (db5). It turned out that the differential optical absorption spectroscopy had a strong anti-interference ability, while the wavelet de-noising method was not suitable for measuring the trace concentration change.

In the exposure process, the intensity and uniformity of light in the exposure area directly influenced the precision of products. UV-LED (Ultraviolet Light-Emitting Diode) exposure system was established to reduce the radiation leakage and increase the energy efficiency for energy saving. It is a trend that conventional mercury lamp could be replaced with UV-LED exposure system. This study was based on the law of conservation of energy and law of refraction of optical field distributing on the target plane. With these, a freeform lens with uniform light field of main exposure area could be designed. The light outside the exposure area could be concentrated into the area to improve the intensity of light. The refraction index and UV transmittance of Polydimethylsiloxane (PDMS) is 1.43 at 385 nm wavelength and 85-90%, respectively. The PDMS was used to fabricate the optics lens for UV-LEDs. The average illumination and the uniformity could be obtained by increasing the number of UV-LEDs and the spacing of different arrangement modes. After exposure process with PDMS lens, about 5% inaccuracy was obtained. Comparing to 10% inaccuracy of general exposure system, it shows that it is available to replace conventional exposure lamp with using UV-LEDs.

A special multiport UV solar simulator was designed at National Institute of Metrology (NIM), and a set of UVA and UVA+B optical filters were developed to satisfy the spectral distribution specifications of COLIPA SPF and JCIA Persistent Pigmentation Darkening (PPD) test methods. The other purpose of this apparatus is used to calibrate the UVA and UVA+B irradiance or dose of broadband UV radiometers. The response of a double grating spectroradiometer with a 5.8 mm entrance aperture from 250nm to 800nm was calibrated using a 1000W spectral irradiance standard lamp at a distance of 500 mm, and the value of quantities of the developed system is traceable to the national primary standard of spectral irradiance of NIM. The system wavelength was checked using a low-pressure mercury lamp. The spectral response of each port was measured from 250nm to 800nm in 1nm steps. Experiment results showed that the percentage relative cumulative erythemal effectiveness (% RCEE) and UVA measurement waveband values of the multiport UV solar simulator are within the specified limits. The source spectrum is smooth and continuous, and the energy below 290nm is less than 0.1%.

For measuring the UV-VIS spectra of single hydrocarbon inclusions, a new micro-spectroscopy system based on inverted microscope and reflective objective was established in this paper. This system includes a reflective objective, a micro-lens, a fiber cable, a 3D adaptor, a spectrometer and a common inverted microscope. The 3D adaptor was perfectly connected with the microscope and no need any rebuilding to the microscope. The reflective objective can be easily con-focused with the objective of the microscope. By the fiber cable, the micro-lens and the reflective objective, the external monochromatic light from the spectrometer was used to excite the inclusions. Using this system, we measured VIS spectra of the inclusions excited by the internal mercury lamp of the microscope. We also measured the spectra of the single inclusions excited by external monochromatic light source. In this case, the influence of the fluorescence of the grain around the inclusion was subtracted from the total spectrum. At the same time, the images of the inclusions were recorded by a CCD camera. Because this system has a low cost, stable and a high sensitive, it is promising to measure the fluorescence of micro-size samples.

Recently, RF driven electrodeless high intensity light sources have been implemented successfully in the projection display systems for HDTV and videowall applications. This paper presents advances made in the RF waveguide and electric field concentrator structures with the purpose of reducing effective arc size and increasing light collection. In addition, new optical designs are described that further improve system efficiency. The results of this work demonstrate that projection system light throughput is increased relative to previous implementations and performance is optimized for home theater and other front projector applications that maintain multi-year lifetime without re-lamping, complete spectral range, fast start times and high levels of dynamic contrast due to dimming flexibility in the light source system.

The study of features of XeBr-excilamp (282 nm) and low-pressure Hg-lamp (253.7 nm) radiation impact on Escherichia coli bacterial culture are presented. It is shown for the first time that both sources of radiation have comparable germicidal action. The prospects of a new bactericidal radiation source - XeBr-excilamp - are discussed.

An efficient and portable method for remote detection of a target mineral material through frequency domain fluorimetry, a detection technique that measures the time lag between absorption and emission of photons, thereby determining the lifetime of said target mineral material. As claimed and disclosed in the present invention, mercury vapor lamps, a common source of industrial facility lighting, emit radiation that overlaps the UV/blue absorption spectrum of many fluorophores and may be used as an efficient and portable excitation source for remote frequency domain fluorimetry.

The lithography prognosticator of the early 1980's declared the end of optics for sub-0.5mm imaging. However, significant improvements in optics, photoresist and mask technology continued through the mercury lamp lines (436, 405 & 365nm) and into laser bands of 248nm and to 193nm. As each wavelength matured, innovative optical solutions and further improvements in photoresist technology have demonstrated that extending imaging resolution is possible thus further reducing k 1 . Several author have recently discussed manufacturing imaging solutions for sub-0.3k 1 and the integration challenges. Our industry will continue to focus on the most cost effective solution. What continues to motivate lithographers to discover new and innovative lithography solutions? The answer is cost. Recent publications have demonstrated sub 0.30 k 1 imaging. The development of new tooling, masks and even photoresist platforms impacts cost. The switch from KrF to ArF imaging materials has a significant impact on process integration. This paper will focus on the usefulness of beyond water immersion for 22nm logic node. Data will be presented demonstrating the impact of higher refractive index photoresist systems have on the further extension of ArF Immersion.

Ultraviolet communication is a new means of free space optical communication links developed since 1990's. In the paper, we first point out the low data rate drawback of the UV communication system using mercury lamp, and find the limitation arises because of the self trapping of the mercury atomic resonance radiation. Then the working principle and the max modulation speed o f the high data rate UV communication system are explained, at last the high date rate UV communication system which based on the low pressure iodine lamp is described in details. The high UV communication system includes an emitter, a receiver and light propagation channel. The light propagation channel is in the low air. Finally, the system has accomplished good voice and high data rate communication in short distance and its maximal communication rate is 48Kbps which decuple the data rate of the UV communication system made by GTE in 2000. Because of shorter wavelength of the iodine UV source, the whole communication system is more suitable for the security communication usage.

The method of the local functional injury of somatic frog's nerve using high coherent UV-A radiation of N 2 laser (λ=337nm, P~10 mW), coherent mercury-vapor lamp radiation (λ=365; 312 nm P Σ ~2 mW/cm 2 ) and low-coherence UV-A sun radiation (400-315 nm, PΣ~10 mW) was realized. The level of injury was assessed from the decrease of compound action potential of the nerve stimulated extracellularly by electrical pulses of millisecond duration. Study of dynamic response of the bundle of axons revealed the decrease of the number of action potential which can be generated (less than 10 5 ). This decrease may be attributed to destruction of action transport and/or voltage-activated ion channels of axon membrane. The dose dependence of the level of nerve injury was studied using varied both intensity and duration of high and low-coherent UV-A irradiation.

We describe imaging the luminance of red fluorescent protein (DsRed2)-expressing bacteria from outside intact infected animals. This simple, nonintrusive technique can show in great detail the temporal behavior of the infectious process. Fluorescence stereo microscope, laser and cooled CCD are expensive to many institutes, we set up an inexpensive compact whole-body fluorescent imaging tool, which consisted of a digital camera, fluorescence filters and a mercury 50-W lamp power supply as excitation light source. The bacteria, expressing the DsRed2, are sufficiently bright as to be clearly visible from outside the infected animal and recorded with simple equipment. Introduced bacteria were observed in the abdomen. Instantaneous real-time images of the infectious process were acquired by using a digital camera by simply illuminating nude mice with mercury lamp. The development of infection over 48 hours and its regression after kanamycin treatment were visualized by whole-body imaging. The DsRed2 was excited directly by mercury lamp with EF500/50 nm band-pass filter and fluorescence was recorded by digital camera with CB580 nm long-pass filter. By this easy operation tool, the authors imaged, in real time, fluorescent tumors growing in live mice. The imaging system is external and noninvasive. For one year our experiments suggested the imaging scheme was feasible, which affords a powerful approach to visualizing the infection process.

Issue of tumor has been a hotspot of current medicine. It is important for tumor research to detect tumors bearing in animal models easily, fast, repetitively and noninvasivly. Many researchers have paid their increasing interests on the detecting. Some contrast agents, such as green fluorescent protein (GFP) and Discosoma red fluorescent protein (Dsred) were applied to enhance image quality. Three main kinds of imaging scheme were adopted to visualize fluorescent protein expressing tumors in vivo. These schemes based on fluorescence stereo microscope, cooled charge-coupled-device (CCD) or camera as imaging set, and laser or mercury lamp as excitation light source. Fluorescence stereo microscope, laser and cooled CCD are expensive to many institutes. The authors set up an inexpensive compact whole-body fluorescent imaging tool, which consisted of a Kodak digital camera (model DC290), fluorescence filters(B and G2;HB Optical, Shenyang, Liaoning, P.R. China) and a mercury 50-W lamp power supply (U-LH50HG;Olympus Optical, Japan) as excitation light source. The EGFP was excited directly by mercury lamp with D455/70 nm band-pass filter and fluorescence was recorded by digital camera with 520nm long-pass filter. By this easy operation tool, the authors imaged, in real time, fluorescent tumors growing in live mice. The imaging system is external and noninvasive. For half a year our experiments suggested the imaging scheme was feasible. Whole-body fluorescence optical imaging for fluorescent expressing tumors in nude mouse is an ideal tool for antitumor, antimetastatic, and antiangiogenesis drug screening.

In this work a preliminary study of the influence of light illumination on the optical constants of chalcogenide thin films with non-stoichiometric Ge19Sb1Te80 composition is presented. Films of Ge19Sb1Te80 with a thickness of ~1 μm were deposited onto glass substrates by vacuum thermal evaporation of parent glasses. The as-deposited films were exposed to light by using a 500 W HBO mercury lamp. The optical constants of the films, before and after their illumination, were evaluated from the ellipsometric measurements in the spectral range of 300 - 820 nm. It has been established that illumination of the films leads to a decrease of the refractive index in the studied spectral region, while a slight increase of the extinction coefficient in the 600 - 800 nm range is observed. For the given film composition the optical bandgap energy of 0.76 eV reduces to 0.62 eV. The film structure shows a very slow recovery expresed in the increase of bandgap energy towards its initial value. The observed decrease of the bandgap energy after illumination is indicative that the film structure undergoes rearrangements upon exposure to light leading to the effect of photodarkening.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

It is well known that pH value and excitation energy have a directly impact on photolysis rate of phenols under Hg-lamp irradiation and oxidation process. The purpose of the current study is the research of o-cresol and para-cresol photolysis in acidic medium under various spontaneous radiation sources irradiation. Photochemical degradation was carried out through a high pressure mercury lamp OΚH-11M, and also with a new capacitive discharge excilamps on working molecules KrCl* (λ~222 nm) and XeBr* (λ~283 nm). Exposure time was varied from 1 to 40 minutes that corresponds radiation doses from 0.5 to 20 J/cm2. A comparison between phototransformations under different light excitation shows that cresol aqueous solutions acidation leads to increase of phototransformations efficiency. It was been found that both in neutral, and in acidic medium the photodecomposition of cresols is carried out more effectively under KrCl-excilamp irradiation.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We are now at a major junction in lithography where non-optical lithographies, such as Electron Projection Lithography (EPL) [1], are being introduced. The mask used in EPL is a non-transparent silicon substrate with a thin silicon (~2m) membrane with openings for electrons to pass through acting as a scatterer. This must be inspected as defects may cause printable defects. Initial mask inspection work has used SEM inspection to find these defects. However, we have historically used optical mask inspection tools, utilising wavelengths at or above what we are using for imaging, to qualify masks. This technology has been increasingly difficult to sustain as we have moved from imaging using mercury lamp based sources to pulsed excimer laser based sources that are not very suited to the inspection imaging. Indeed, review of defects found has moved from optical microscopes to SEM based tools. Inspection tools have also evolved, with the first SEM based mask inspection tools being developed to find the smallest defects, however these have the penalty of very low throughput. We will show the potential of using optical systems for the transmissive inspection of these EPL masks. The high potential of existing tools will be shown together with the need for a next generation of inspection tools. We will show that simulations indicate that an inspection source with 193nm wavelength would be required for the detection of 50nm defects on a mask used to print 70nm dense lines. It will also be shown how the position of the defect within the membrane greatly influences detection as well as the implications of moving to a thinner silicon membrane.

Ideal for automation, a new kind of UV spot/wand curing system that lowers per unit bonding costs is based on a very short arc, high-pressure mercury lamp. (Note: Lamp are sometimes incorrectly referred to as light bulbs. A spot/wand curing system includes the lamp, a power supply, reflectors, lightguides and shielding.) Called the BlueWave™, this curing system provides as much as 45 W/cm 2 of actual curing power through a long lived, filtered lightguide. New design options have resulted from this new level of intensity, unique wavelength distribution and long operating life. In addition to at least 2,000 hours of operating life, effective costs are lowered even more by replacing 2, 3 or 4 100 Watt spot cure systems with a single 200 Watt Enhanced Short Arch Mercury Lamp (ESAM) in a 4-pole multiple lightguide system. Additionally, the very high intensity allows the use of rod lens assemblies that provide uniform curing intensity in areas up to five inches square.

It has recently been demonstrated that collagen is a very effective upconverter of light by second harmonic generation (SHG) but hitherto the potential this offers for biomedical imaging has not been realized. We show that bright SHG images van be obtained over a wide excitation range at illumination levels comparable to or lower than those required for two-photon excitation of fluorescent labels, with no damage to the collagen structure. Both paraffin and cryostat sections have been used, and medically significant results have been obtained in several fields. We show that the signal is easily distinguished from single and two-photon excited fluorescence by its forward propagation and narrow spectral width; in principle it could also be distinguished by lifetime. Key microscope requisites are: immersion objectives and condensers, high-efficiency PMT detectors for transmitted light, suitable filters, and effective blocking of stray light, especially from the mercury lamp.

The amorphous GeS2 film is one of the chalcogemde glass and also shows the phenome-non of Ag-photodoping under the illumination of the high-pressure mercury lamp. We havebeen carrying out the in-situ measurements of the photodoping process of Ag/a-GeS2 filmssystem with a laser probe effipsometer. In the process of the thickness measurements, wehave observed curious changes of ellipsometric parameters A and W of the GeS2 filmsample during the illumination of the laser probe. The results seem to be suggesting that theillumination of the laser beam might engrave the GeS2 film. The power of the laser is lessthan 1mW and the beam diameter is 1mm. The idea such as an ablation of the GeS2 filmseems to be unlikely to interpret this phenomenon.Keywords: ellipsometry chalcogenide glass, thin films

One of the most important technical driving forces for IC manufacturing is lithography. IC manufacturing equipment is required to work in sever full-time operation, such as 24 hours a day and 7 days a week. KrF laser, however, has established its status, and has proven the applicability of excimer laser itself. The transition from super high pressure mercury lamp (i-line:365nm) to KrF laser was a natural trend, because the resolution is improved proportionally with shorter wavelength. Practical resolution is now said to attain half the wavelength, using high NA optics and imaging tricks, such as phase shifting masks, oblique illumination, etc. At present, 130nm resolution is pursued using a KrF laser and a projection lens whose NA is nearly 0.7. ArF laser lithography is also under extensive development. In the initial stage, it has proven 120nm resolution with an NA 0.6 projection lens, and now aims at 100nm resolution of 4G-bit DRAM as the next generation. The light source development always comes first in lithography, and F2 laser technology is now paid much attention.

The standard of luminous intensity unit, which is built on the base of the cryogen absolute radiometer and stabilized on the mercury lamp as monochromatic radiator, is described in here. The root-mean-square deviation of the random component of an error was roughly 0.1%. The system of unit transfer permits to pass to the characteristics of a continuous spectrum.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Compact LCD projectors require compact, low power metal halide lamps to achieve maximum screen brightness. We have previously described such lighting systems, taking into account ballast stability, source etendue, and collection optics. Metal halide sources have a significant advantage over high pressure xenon, high pressure mercury, and halogen sources in that the spectral power distribution of the source can be optimized for the projection system. This is in addition to the inherently greater luminous efficacy of metal halide source. We present the result of recent studies on chemical dose composition in 50 Watt, 1.2 mm arc gap, long life metal halide lamps. Through designed experiments on chemical species, dose weight, and molar composition we were able to increase the luminous output by as much as 50 percent in some cases. The optimized metal halide lamp has 50 percent more red radiation than a 50 Watt, 1.3 mm gap high pressure mercury lamp and also produces a preferred color temperature. Knowledge of the significant factors that effect color allows us to design virtually any color gamut. It was possible to match the filter characteristics of a number of projection systems.

We report studies on photobleaching process of polymer waveguides by means of a high pressure mercury lamp. After considering the film shrinkage and the surface index in the bleaching front, an inversed treatment based on the improved WKB method was employed to determine the index profiles of the bleached polymer film using experimentally measured mode indices. Index profiles presented in this paper are consistent with the photobleaching kinetics.

Chip makers are gearing up for 686-class micro-processors and 64 Mb production. These require producing < 0.30 micrometers critical features. They are also focusing on 256 Mb DRAMs that require below 0.25 micrometers design rules. Therefore, the shift from mercury lamp based i-line to 248 nm Deep-Ultra- Violet (DUV) steppers has begun in earnest. Current KrF laser models from several suppliers satisfy the optical requirements necessary for pilot production. However, as the move from DUV lithography R&D environment to production occurs, the laser's manufacturability, uptime requirements and cost-of-operation (CoO) become more demanding. The chip maker requires reliability, availability and maintainability data from laser manufacturers to support uptime and CoO estimates. Often, such data are required long before the lasers actually go into production.

Two fluorescence sensors that are much simpler and less expensive than conventional laser based devices have been developed. The sensors are designed to be deployed in cone penetrometers, utilizing a mercury lamp in the cone for excitation of either a down-hole filter- photomultiplier combination or an up-hole multichannel spectrometer for detecting emission. Both sensors are demonstrated to be useful for rapid, in situ detection of fuels at concentrations ranging to below 100 ppm (a typical action level for cleanup) in soil.

An aging process that makes SiNx single-layer halftone film stable for DUV (248 nm) exposure has been established. The light irradiation with a low pressure mercury lamp was used to age the SiNx halftone film from the tendency of the transmittance change caused by the DUV exposure. Taking account of the optical constants shift during aging process, a SiNx halftone film with transmittance T equals 9.3%, phase shift angle (theta) equals 178 degrees was obtained. At the SiNx film, no transmittance change was observed after 2800 J/cm2 DUV exposure. Using the mask, 0.2 micrometers hole patterns were obtained with above 1.0 micrometers depth of focus (DOF).© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper describes the contact copying of amplitude transmission holographic gratings. Master gratings (MG) are written in silver halide sensitized gelatine. A smooth and flat sheet is coated with a layer of negative photoresist constituted from a combination of polyvinyl alcohol, ammonium dichromate and Arabic gum, then the MG is put in contact with the metal surface and exposed by a mercury lamp. After processing with deionized water at (35 degree(s)C), a reflection grating is obtained. For a MG with 117 l/mm of spatial frequency and 10% of diffraction efficiency (DE), we have obtained a DE of 12%.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A new spectrometer (EMPHO IIb) for measurements of NADH fluorescence spectra in tissue was developed which enables recording of 100 spectra per sec. by use of a rotating filter disc. The excitation of fluorescence is induced by a mercury lamp (HbO100 W/2) at 366nm. For the optical coupling of the instrument to the surface of tissues quartz microlight guides are applied.

The instrument for measuring the light scattered from optical surfaces is described. The measurement is carried out using the 253 nm wavelength separated from continuous spectrum of high pressure mercury lamp by a double monochromator. Output signals are detected by a photomultiplier whose sensitivity falls rapidly above 300 nm. The sensitivity of the instrument is about 0.5/3 X 10

The mechanisms of UV induced decomposition of oxygen-deficient centers (ODC) in silica glass has been experimentally studied. It is shown that high intensity irradiation of silica glass results in the two-step decomposition of ODC and formation of paramagnetic E' centers. At the same time at low UV irradiation intensity (laser, mercury lamp) the single quantum reaction of ODC with gas-phase impurities in the net of silica is the dominant process of ODC photoreaction.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Three-dimensional lithographic patterns can be obtained using a new two component UV sensitive polymer system. The light-sensitive material consists of a chlorine containing conventional polymer, i.e., poly(chloroacrylonitrile) as a typical acceptor, and a heterocyclic or aromatic monomer as the donor, here pyrrole. This two component precomposite can be irradiated by either an excimer laser or the radiation of a high pressure mercury lamp. The resulting image, essentially a black and white pattern, can be developed in wet or dry (ion etching, ablation) modes giving resist patterns with a resolution in the micrometer range.

A potassium vapor arc lamp has been developed for use as the optical pump source in a Nd:YAG space communications laser. The 250 W dc, sapphire envelope lamp is significantly more efficient than conventional optical pumps such as krypton arc lamps and tungsten in-candescent lamps at laser power levels required for the space communications application, is longer lived, and is ruggedized to survive a spacecraft launch environment. The lamp has a compact single envelope configuration and is capable of operation in ambient air. In this paper features of the lamp design are described and lamp performance characteristics are discussed.© (1978) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

High speed photography requires, in addition to a good color quality of the light source, a very high level of illumination. Conventional lighting systems utilizing incandescent lamps or other metal halide lamp types has inherent problems of inefficient light output or poor color quality. Heat generated by incandescent lamps and the power these sources require drive up operating and installation costs. A most economical and practical solution was devised by using the metal halide discharge lamp developed by OSRAM, GmbH of Munich, West Germany. This lamp trade marked the HMI Metallogen® was primarily developed for the needs of the television and motion picture film industry. Due to their high efficiency and other consistent operating qualities these lamps also fulfill the needs of high speed photography, e.g. in crash test facilities, when special engineering activities are carried out.The OSRAM HMI lamp is an AC discharge metal halide lamp with rare earth additives to increase both the efficiency and light output qualities. Since the lamp is an AC source, a special method had to be developed to overcome the strobing effect, which is normal for AC lamps given their modulated light output, when used with high speed cameras, (e.g. with >1000 fps). This method is based on an increased frequency for the lamp supply voltage coupled with a mix of the light output achieved using a multiphase mains power supply.First developed in 1977, this system using the OSRAM HMI lamps was installed in a crash test facility of a major automotive manufacturer in West Germany. The design resulted in the best lighting and performance ever experienced. Since that time several other motor companies have made use of this breakthrough. Industrial and scientific users are now considering additional applications use of this advanced high speed lighting system.Part I Introduction and lamp characteristic backgroundFor over 30 years the advantages of using mercury vapor lamps have been well known because of their high luminous efficacy and electrical efficiency. However, it has only been in the last 15 years that lamps of this type termed metal halide lamps have been developed that combine both high efficiency and good color rendering. Color photography requires a source which has excellent color rendering and reproducibility in the standard daylight spectral region. Basic research into metal halide technology to create a lamp that had both high luminous efficacy and excellent color rendition in the daylight region became the target goal for a basic research program begun by OSRAM in the mid-60T s. By 1969 a source was developed which was acceptable for use by the West German television system which had a color rendering index of greater than 90 and could faithfully reproduce daylight color temperature. The special lamp which came out of this research was tagged the OSRAM HMI Metallogen® lamp, now a family of 6 lamps.These lamps are a member of the metal halide type, high intensity discharge (HID) lamp family and are currently available in the 200, 575, 1200, 2500, 4000 and a newly developed 6000 watt size. (Fig. 1) The lamps are primarily filled with Argon, as a start­ ing gas, and Mercury as basic elements to achieve an arc discharge within the vessel. As with other metal halide additive lamps, rare earths have been incorporated into the arc vessel to provide the full spectrum of energy in the visible region. With the HMI lamp however, the metals employed provide a multi-line spectrum which appears as continuous radiation throughout the visible range due to the large number of emission lines radiated by the rare earths involved. (Fig. 2)To achieve improved color quality and higher efficacy as compared to other standardHID lamps the vapor pressure on the HMI lamps was increased. The resultant wall loadingis comparatively high, about 100 watts per square centimeter. Physical construction of

Knowledge of both acute and chronic biological effects is currently used to evaluate lamp safety. In some cases, a quantitative basis for avoiding exposures greater than a certain value can be stated. In other cases, however, only a qualitative estimate of the hazard is available. In a discussion that uses mercury vapor lamps, tanning booths, and sodium vapor lamps as examples, the interplay between the two types of data leading to an evaluation of lamp safety is described.

Discharge lamps filled with xenon gas through which electrical capacitors are discharged have found many applications for producing pulsed energy in photography and energy discharges. The object of this paper is to review sane of the more important characteristics of flash lamps. The flash duration of specific flash lamps when operated from a given capacitor charged to same known voltage is dis-cussed below. The dimensions of the lamp are one of the most impor-tant factors since the response of the lamp to the circuit is greatly influenced. Experimentally measured flash duration as a function of capacitance and voltage is given in graphical form for one type of flash lamp. Rules (approximate) are given for converting the data into data for other flash lamps and circuits. Efficiency of a xenon lamp can be as high as 5 candela/watt for a lamp that is loaded so that the arc fills the inner diameter of the constraining tube. The life of the xenon lamp can be many, many flashes. In fact, this is one of the lamp's strong points. The spectral distribution of the light from a xenon lamp closely approximates daylight with a small shift to the blue if the applied voltage is high. Details of a specific flash lamp showing the nature of the spectral output is given. A list of some of the oractical uses of electronic flash lamps is given and discussed.

High pressure xenon arc lamps produce a compact arc characteristically less than 10mm in length. The nearly 6000 degrees K color temperature closely approximates that of sunlight at 5900 degrees K.

Single parameter irradiance measurements commonly used for the determination of photo-resist exposure times are incapable of giving unique values of either the broad band irradiance from a mercury-arc lamp, or the photoresist exposure times. Resolution of these measurement incapabilities through a series of irradiance measurements of narrow, approximately monochromatic radiation bands is discussed. A basis for establishing photoresist sensitivity indices that can be used to calculate. unambiguous exposure times by applying Van Kreveld's additivity law to these narrow band irradiance measurements is suggested. The thickness variation of photoresist films is included in the method of calculating exposure time. Conditions that may simplify the calculations of exposure times or reduce the number of irradiance measurements when a mercury lamp is used as the exposure source are discussed. Suggestions are made for the use of these indices as photoresist specifications, and for the real-time automatic monitoring and control of exposure times in wafer fabrication where optical density variation in the photomasks and thickness variations in the photoresist films are automatically incorporated into the control by a microprocessor.

Reticles (masks on enlarged scale) are needed for optical pattern transfer in the production of integrated semiconductor circuits. In order to meet present requirements for 5X reticles only a direct writing technique is feasible. This means direct exposing of photoresist either with light or an electron beam. Many of todays highly dense reticles require some 10 5 to 10 6 discrete exposures when generated with an optical pattern generator. Optical pattern generators normally use mercury arc lamps to expose positive photoresist, which in turn need 200 milliseconds for each of these discrete exposures, thus requiring to stop the table at every exposure position ("stop and go" mode). This results in running times of several days per reticle. Therefore most reticles are nowadays being manufactured with very expensive e-beam machines. In the early 80's we started the first experiments to expose photoresist with an excimer laser. In order to obtain the maximum gain in speed, the goal was to operate with only one excimer laser pulse per exposure, so that a fast "flash on the fly" operation with an optical pattern generator became true. Equipping a conventional optical pattern generator with an excimer laser as the light source, it has become possible to expose substrates coated with standard photoresist in the "flash on the fly" mode with only 13 nanoseconds per flash. So the thruput could be increased up to 25 times in comparison to a pattern generator equipped with a mercury lamp. A comparison of both operation modes will show that an immense increase of speed is possible, even when a ten years old M3600 pattern generator is used. This system is in function now with very high reliability since more than three years in our IC development line.