Abstract: The illuminator apparatus disclosed herein provides illumination for the microlithographic manufacture of semiconductor integrated circuits. Degradation of the illuminator output by photopolymerization of volatile compounds associated with the resist coatings is inhibited by utilizing a composite filter at the cooling area inlet to the light source which includes a bed of activated carbon for removing volatile compounds which are photopolymerizable to substances which are absorbtive at the exposing wavelengths.

Abstract: An ultraviolet lamp for use in a water purifier has two pairs of terminal pins mounted on, and extending outwardly along a longitudinal axis of, one of the end caps of an arc tube. The pairs of pins are offset relative to each other along the longitudinal axis to resist electrical arcing between the pairs of pins exteriorly of the arc tube. An internal barrier wall resists electrical arcing within the one end cap.

Abstract: The present invention comprises a process for the removal of oxides of nitrogen and sulfur from a gas mixture containing those species by exposure of the gas mixture to ultraviolet radiation having a wavelength below 220 nanometers.

Abstract: The irradiation device for drying and/or curing paints, varnishes and similar coatings (13, 14) has at least one UV high-power radiator having a discharge space (3) filled with filling gas. The filling gas contained therein emits radiation under the effect of silent electrical discharges. The discharge space (3) is bounded by walls (1, 2), at least one wall consisting of dielectric material and being transmissive to the radiation generated in the discharge space (3). A pair of electrodes (4, 5), with an AC source (10) connected to the two electrodes, serves for feeding the discharge. The treatment space (6) is immediately adjacent to the dielectric (1, 2). The electrodes (4, 5) are positioned at a distance from the immediately neighboring dielectric. The coupling of the electrical energy from the electrodes into the discharge space takes place essentially capacitively.

Abstract: A method and means for generating synthetic spectra allowing quantitative measurement utilizes dual chip alternatively energized IREDs with optical bandpass filter(s) passing two optical bands which could be combined with curvilinear interpolation to be utilized in a low cost small size quantitative measuring instrument.

Abstract: Disclosed is an apparatus for forming aesthetic artificial nails by curing a jelly-like visible light-curable resin applied thinly on the fingernails, including: a casing having disposed therein a power circuit containing an inverter circuit, a light source section connected to the power circuit and irradiates visible light, and a slide table on which the finger tips with the fingernails being coated with the jelly-like resin is rested; wherein the light source section is made into a unit consisting of a plurality of small fluorescent lamps, each of which may have a triggering proximate conductor arranged on the same horizontal plane of a substrate in which a card edge terminal to be connected to a card edge connector in the power circuit is integrated and a transparent protector disposed in front of the fluorescent lamps; the slide table being slidably disposed below the light source section so that it can be drawn out of the casing.

Abstract: A target placement apparatus having the facility to select targets with apertures of various sizes and monitor their temperature by pressing them against a framework. The apparatus is adapted to place targets at the objective plane in an infrared sensitivity or calibrator. The apparatus comprises a magazine-like storage means for storing a plurality of target plates, preferably soaking at ambient temperature, and a mechanical arrangement for removing a selecting one of the target plates from the storage means and precisely placing it at the objective plane. The arrangement for removing a selected target plate from storage and placing it in the proper position includes a movable mechanical arm having a simplified wrist action which positively and reliably operates to remove a selected target plate from the storage means and swing the target plate into an indexed position within a window area of a surrounding high mass framework.

Abstract: An aftertreatment apparatus, for printing plates which have been exposed imagewise comprises an exposure station and a heat station which are disposed one behind the other in the direction of conveyance of the printing plates along a conveyor track through the aftertreatment apparatus. The exposure station contains a regulable radiation source for the total area exposure of the printing plates. The housing of the exposure station has an exposure aperture 13 which faces downwardly and which is covered by a filter disc. The housing of the heat station is thermally insulated at three sides and is open downwards in the direction of a reflector table across which the printing plates are fed.

Abstract: Light-transmitting contact lenses of Polymethylacrylate, Gas Permeable of Hydrogel materials may be immersed in an aqueous liquid medium contained in a storing and processing device, all of which are substantially transparent to the ultraviolet radiation spectrum. The lenses, liquid medium and storing device are all irradiated with ultraviolet radiation in a preselected frequency range, while simultaneously being subjected to ultrasonic frequency vibrations to thereby cause asepticization of lenses, liquid medium and storing device. The ultraviolet irradiation and ultrasonic vibrations are insufficient to cause detrimental molecular modification to the lenses or storing device, but does cause the formation of oxidation free radicals in the liquid medium. The unique combination of ultraviolet irradiation and ultrasonic vibration in the presence of the liquid medium containing oxidation free radicals cause rapid destruction of all microorganisms associated with the lenses, liquid medium and storing device.

Abstract: A far infrared ray emitting, odor-absorbing material is disclosed. The material comprises cellulose acetate fiber having adhered thereto an ultrafine powder of alumina hydrate or silica hydrate which is chemically produced in an aqueous dispersion of the cellulose acetate fiber. The material possesses a high far infrared ray emitting, odor-absorbing capability as well as many characteristics inherently possessed by cellulose acetate fibers, and can expand the utility of cellulose acetate in such fields as sanitary, health-care, and medical fields.

Abstract: A compact automatic apparatus for rapidly curing photosensitive coatings on eyeglass lenses. A precision adjustable automatic programmer controls process cycling, ultraviolet intensity and radiation time. A control panel is used to switch the apparatus on or off and to manually select cycle parameters. The apparatus electronically monitors radiation intensity and uses a flashing light to warn the operator of low ultraviolet intensity. Apparatus components are cooled by a filtered force air convection system that prevents flow of unfiltered air into the apparatus. An automatically programmed linear motion lens transport carriage passes through an automatic outer door which allows inward and outward passage of the lens while protecting the operator from ultraviolet radiation. The outer door shields the machine interior from dirt and dust.

Abstract: Pivotable, reflective target elements are used to reflect infrared radiat from blackbody sources and transmit the radiation toward infrared-detecting device to test the capability of the device to detect patterns of infrared radiation under dynamic field environment.

Abstract: A radiant drying system includes a radiant energy source such as a lamphead with a mercury vapor lamp which produces radiation in the infrared and ultraviolet spectral ranges. Water-filled tubes extend through the lamphead below the lamp for filtering some of the infrared radiation. A housing or filter assembly is mounted on the bottom of the lamphead and includes downwardly-diverging walls and a bottom enclosed by a light-transmitting lens, which filters the ultraviolet radiation to reduce the output thereof in the "B" (beta) range. A fluid system circulates water through the lamphead and air through the housing assembly.

Abstract: Drawn optical fiber is provided with at least one layer of a coating material. The coating material typically is a UV curable material and provides the optical fiber with mechanical and environmental protection. It has been found that the temperature at which the optical fiber is cured has a pronounced effect on the modulus of the cured coating material. In order to provide a coated optical fiber of which the coating material has a desired modulus, the temperature of the coating material during cure is controlled by controlling the amount of energy of infrared wavelength which impinges on the coating material.

Abstract: A target system adapted for use in a cassegrain reflective optical collimator system comprises a single target pattern including at least one visible target, at least one near infrared target and at least one far infrared target. This single test target pattern is joined to a heat-transmitting target support member positioned behind the target pattern, to a heater behind the heat-transmitting target support member, to an insulator behind the heating means, and to an illuminator for each of the targets in the single target pattern behind the insulator plate. The elements of the target system are cemented together in precise registration to form a rugged reliable unit that is low in cost, and that includes all the targets in a single focal plane positioned precisely and as accurately as one micron, which results in optical angular position accuracies of at least 20 microradians when the target is positioned in a long focal length optical system.

Abstract: An infrared tracker for tracking a carrier in clutter comprises a pyrotechnically heated emitter, a beam concentrator, and a blanking means all of which are mounted on the carrier, and a command link, a thermal detector, a display signal storage means, a display, and a comparator all of which are located remotely to the carrier, said command link operative to provide an emitter start-up signal and a blanking command signal, said emitter and blanking means operative in response to the command signals sent to the carrier when there is clutter present that might be confused with the carrier, respectively, to actuate the emitter and blanking means, said display storage means operative to store a first video frame of the carrier while the emitter is blanked out, and said comparator for ocmparing the first video frame without the emitter to a subsequent video frame including the emitter to distinguish between the clutter is being substantially canceled.

Abstract: A night vision goggle capability evaluation apparatus useful in assessing the degree of illumination present in a proposed NVG operating environment is disclosed. The evaluation apparatus includes portable illuminator and detector devices that are battery operated and optionally coupled to the input and output ports of the goggle during both their own calibration and during measurement of the proposed operating environment. The disclosed apparatus operates by calibrating the NVG output measuring detector from the saturated and dark output extremes of the NVG system and then using this calibrated detector to measure the output of the NVG system and determine whether is it receiving adequate light for satisfactory performance.

Abstract: A thermal target which produces and emits an infrared image that simulates heat emitting equipment or personnel, wherein said image is formed by an electric current passing through a heatable resistive coating integral with the target, wherein said thermal target is comprised of a structural sheet, that is weather resistant and flame resistant, which is covered with an insulative coating onto which is applied an electrically resistive coating, which when heated creates an infrared image, where said resistive coating is in electrical contact with a conductive coating which distributes current over the target and is in electrical contact with a power supply.

Abstract: A gas detector system for detecting gases such as CO.sub.2. Sample air is passed through a critically sized sealed sample chamber in a sample cell. Infrared waves are generated in an insulated heater assembly, and radiate through windows of the sealed sample chamber concurrent with the sample air. The strength and magnitude of the infrared waves is attenuated by the level of gas, such as CO.sub.2, present in the sample air passing through the critically sized sealed sample chamber, and is sensed by a thermopile detector, including a filter for a specific frequency of infrared energy. Electronic circuitry processes the thermopile signal and measures other parameters of the gas detector to provide a signal indicative of the percentage of gas concentration in the air. Extensive use of insulation about and around the thermopile detector electronic circuitry and other components of the detector maximize stability and reliability.

Abstract: Containers (20--20) which held UV curable acrylate materials commonly used as coating materials for drawn optical fiber are treated prior to disposal. Because of the presence of acrylate residues therewithin, the container cannot be disposed of in a landfill and has been incinerated. This problem has been overcome by exposing the residue within the container to suitable reproducible radiation determined in accordance with the photochemistry of the residue materials to cure completely the remaining acrylate material and thereby reduce its reactivity.

Abstract: Devices for illuminating a target with a beam of coherent energy. The device has a number of applications. In one, it is employed with a night vision system to make available additional energy which can be utilized by an image intensifier in the night vision system in prodcing a visual image of a target acquired by the night vision system.

Abstract: A source of infrared radiation or an infrared radiator is disclosed for use in surveillance systems, and the like. The infrared radiator comprises a light source for providing a beam containing infrared radiation and a radiation filter disposed in the path of the beam to selectively pass only the infrared radiation. The light source and radiation filter are disposed within an inner housing which is in heat transfer proximity thereto. The inner housing is configured to contain visible light within the inner housing and permit infrared radiation to exit only through the radiation filter. An outer housing having openings formed therein is disposed about the inner housing such that a portion of the outer housing is spaced from the inner housing to define a path for air between the openings. In a preferred embodiment, a cooling means is located within the outer housing to force exterior air along the path, allowing heat absorbed by the inner housing to be dissipated.

Abstract: Devices for illuminating a target with a beam of coherent energy. The device has a number of applications. In one, it is employed with a night vision system to make available additional energy which can be utilized by an image intensifier in the night vision system in producing a visual image of a target acquired by the night vision system.

Abstract: Devices for illuminating a target with a beam of coherent energy. The device has a number of applications. In one, it is employed with a night vision system to make available additional energy which can be utilized by an image intensifier in the night vision system in producing a visual image of a target acquired by the night vision system.

Abstract: An improved beacon assembly 30 for use with a beacon 34 for providing radiant energy. The invention 30 includes a single plate 32 having an open interior to provide a frame through which the radiant energy from said beacon 34 may pass and apparatus 36 for mounting the plate 32 and the beacon 34 to the missile 10.In a more specific embodiment, the plate 32 is constructed of aluminum and has arcuate inner 42 and outer 44 peripheries connected by substantially straight sections 46 and 48 to provide a pie shape with a pie shaped piece removed from the small end thereof to provide a frame through which the radiant energy from the beacon 34 may pass.The improved beacon assembly of the present invention 30 affords a low cost lightweight retrofit of existing missiles with a thermal beacon 34.

Abstract: Apparatus for disinfection of lavatory instruments, medical instruments or the like, through ultraviolet radiation, wherein the instruments are arranged within a housing in combination with a mounting plate and irradiated by a light source which generates UV-radiation. The apparatus is designed to achieve the highest possible degree of effectiveness with a shadow-free irradiation of the instruments to be treated with simple manipulation of the apparatus. A receiving vessel with a take-up frame is insertable in the mounting plate, and the housing provided with openings is pivotable and engageable on arms of the mounting plate.

Abstract: An exposure apparatus for color cathode ray tube having a single faceplate with a phosphor screen on an inner surface thereof comprises light source device including an initial light source for emitting ultraviolet light, exposure device including a base for supporting the faceplate with a photosensitive layer having a plurality of sub-regions to form the phosphor screen, a plurality of secondary light sources emitting exposure light for exposing corresponding sub-regions and moving device for shifting position of the secondary light sources, and light distribution device for equally distributing a part of ultraviolet light emitted from the light source device to the secondary light sources.

Abstract: Ultraviolet light curing of a composition on a unit such as an aircraft canopy includes an ultraviolet light generator mounted for movement in at least three directions of motion relative to the unit. The generator is selectively movable in relation to the unit according to prerequisite procedure. A regulated environment cell is provided for the curing. The ultraviolet generator follows predetermined sequences and can be located partly within the canopy during curing. The canopy, after being mounted on a mobile fixture in the horizontal position is pivotally turned to be vertically located strategically relative to the ultraviolet light source during curing.

Abstract: An infrared scene projector has a cathode ray tube with a display screen coated with a luminescent phosphor material that produces radiation in the infrared spectrum when excited by the electron beam. The desired screen images are generated electronically, the screen is scanned by the cathode ray beam, and the intensity of the beam is modulated by the signal from the image generator.

Abstract: A system for monitoring moving objects, such as the flight of honeybees and other insects, using a pulsed laser light source. This system has a self-powered micro-miniaturized transmitting unit powered, in the preferred embodiment, with an array solar cells. This transmitting unit is attached to the object to be monitored. These solar cells provide current to a storage energy capacitor to produce, for example, five volts for the operation of the transmitter. In the simplest embodiment, the voltage on the capacitor operates a pulse generator to provide a pulsed energizing signal to one or more very small laser diodes. The pulsed light is then received at a receiving base station using substantially standard means which converts the light to an electrical signal for processing in a microprocessor to create the information as to the movement of the object. In the case of a unit for monitoring honeybees and other insects, the transmitting unit weighs less than 50 mg, and has a size no larger than 1.times.3.times.

Abstract: A method is described for reducing atmospheric or global warming resulting from the presence of heat-trapping gases in the atmosphere, i.e., from the greenhouse effect. Such gases are relatively transparent to sunshine, but absorb strongly the long-wavelength infrared radiation released by the earth. The method incudes the step of seeding the layer of heat-trapping gases in the atmosphere with particles of materials characterized by wavelength-dependent emissivity. Such materials include Welsbach materials and the oxides of metals which have high emissivity (and thus low reflectivities) in the visible and 8-12 micron infrared wavelength regions.

Abstract: An infrared source suitable for use as a remote source for infrared interferometer spectrometers. This device is composed of a heat source, a black body radiating element and a concave reflector. A support to maintain the heat source and black body radiating elements in proper position is also preferably included. The device of the present invention enhances the accuracy and sensitivity of gas sensing devices based upon measurement of background infrared radiation, and allows the remote infrared source to be used in locations in which ignitable materials may be present.

Abstract: A system for curing a photosensitive coating on a moving substrate comprises a dual-fluid cooled reflector block and ultraviolet lamp assembly, first and second intermediate pressure blowers connected in series, a heat exchanger, refrigerating device connected in an appropriate manner to the reflector-block lamp assembly and a computer. The reflector block has a cavity with a reflective surface, a channel extending longitudinally of, and open to, the cavity for a substantial portion of its length and both an air and a water conduit extending longitudinally of the block. The lamp is mounted within the reflective block cavity and the air conduit connects through ports with the cavity channel.

Abstract: A device is divulged for generating an infrared image, in which an electron beam having a section substantially equal to the area of a pixel formed from a material having high emissive power in the infrared, directly bombards this material. The energy of the beam is transformed into heat then into infrared radiation, in the material. Each pixel is supported by a slab of a material transparent to the infrared, which is heat insulating and deposited on a screen transparent to the infrared and heat conducting.

Abstract: An optical clutter scene stimulator generates a scene simulating atmospheric optical clutter produced by a nuclear event. The stimulator focuses a display source scene on a focal plane, then displaces the scene from the focal plane so as to provide a scene representing optical clutter. Alternately, the optical clutter scene can be generated by performing an optical Fourier transform.

Abstract: The invention relates to a drying section which includes UV-light generating devices for drying a coloring substance applied to a material, for instance, colored print applied to print material and a silkscreen printer, and further comprising a conveyor for conveying the material passed one or more of the UV-light generating devices. The UV-light generating devices are cooled and a light and gas permeable grid is arranged between the material and each UV-light generating device. The grid has the form of three glass plates which define therebetween a plurality of apertures defined by recesses formed in the edge margins of respective glass plates.

Abstract: An ultra violet rays generator by means of microwaves excitation which comprises a microwave generator for generating microwaves, a microwave cavity directly connected to said microwave generator, an ultra violet ray (UV) reflector having a window for introducing microwaves on the upper part thereof, detachably secured in said microwave cavity, and an ultra violet rays lamp disposed under said window and near the inside of said UV reflector, said UV reflector being composed of a light-transmitting base, and an inteference film formed on said base. According to the generator, it is detachable of only the UV reflector without changing the capacity of the microwave cavity, and thus becoming changeable of only the directions or configurations of the UV without changing microwave efficiency of the microwave cavity, and furthermore, it can obtain the UV of low temperature, exclusive of infra red rays originally included in the UV.

Abstract: This invention relates to an apparatus emitting electromagnetic radiation, particularly infrared, which comprises a cylindrical source of rays and a reflector. In order to avoid the problem due to captive rays and to multiple reflections, the cross section of a half-reflector comprises, starting from the plane of symmetry, a first curved part constituted by an arc of involute to a circle extending from the plane of symmetry to an end located on a first extreme ray tangential to the source and passing through a first end of the target and a second curved part joined tangentially to the first curved part and of such shape that all the tangential rays emitted from the cylindrical source and falling on this second curved part are reflected towards the first end of the target located on the other side of the plane of symmetry.

Abstract: Fingernail light systems for curing photopolymerizable plastics on fingernails are known, having a housing with a bottom plate 7, in which housing a support body 4, having indentations 18 on its outer contour, is provided for positioning the fingers of the hand 5 to be irradiated, and having at least one irradiation lamp 14, which at least partially surrounds the support body in a spaced-apart manner in the irradiation position, the support body being accessible in the irradiation position via an opening 10 in the housing.

Abstract: Light systems, in particular for curing photopolymerizable plastics on fingernails, are known which have an irradiation chamber in which one or more irradiation lamps are located and having a fan for ventilating the irradiation chamber, the fan being located in a region of the housing partitioned off from the irradiation chamber. To provide a light system, in particular for irradiating artificial fingernails, that has an adequate forced ventilation of the irradiation chamber regardless of the position of the fan in the housing and regardless of the flow courses, while still being compact in structure, an air distribution chamber is provided between the irradiation chamber and the suction or compression side of the fan. The air distribution chamber is partitioned off from the irradiation chamber by a wall having air openings, and with increasing distance from the suction or compression side of the fan, the cross-sectional area for the passage of air to the air treatment chamber is greater.

Abstract: A system for improved cooling of a photosensitive coating on a moving substrate comprising a reflector block and ultraviolet lamp assembly, a refrigerating device, water circulation system and control system. The reflector-block includes two longitudinally extending cooling conduits and is substantially completely cooled by refrigerated water circulated through such conduits within a temperature range monitored and regulated by the control system.The method of this invention comprises controlling the temperature of the reflector-block of the apparatus for curing of a photosensitive coating on a moving substrate. The reflector-block is operated at a temperature range between about 50.degree. F. to 90 .degree. F. by water circulated through the reflector-block conduits, which water is cooled by a refrigerating device to a temperature within a range between about 45.degree. F. to 75.degree. F.

Abstract: The specification discloses an apparatus and method for repelling insects through the generation of only far infrared electro-magnetic waves in the range 50 microns to 1000 microns in length.

Abstract: To provide for essentially uniform ultraviolet (UV) irradiation of all the nails of all the fingers of a hand of a user, a radiation source of essentially horseshoe shape is placed within a housing. The plane, in which the radiation source is located, is inclined with respect to the bottom wall (2) of the housing, on which the hand of the user is supported. The radiation is directed to impinge on the nails at about 90.degree.. The nail of the thumb also has radiation impinging at about 90.degree.. The radiation source may be a single, bowed, UV-emitting lamp, or may be built-up of straight lamp sections (12,13), e.g., two lamps along the housing sides for irradiating the thumbs, and one or two lamps across the housing to irradiate the nails of the index finger through little finger.

Abstract: Deep UV projection lithography can be performed using an e-beam pumped solid excimer UV source, a mask, and a UV reduction camera. The UV source produces deep UV radiation in the range 1700-1300A using xenon, krypton or argon; shorter wavelengths of 850-650A can be obtained using neon or helium. A thin solid layer of the gas is formed on a cryogenically cooled plate and bombarded with an e-beam to cause fluorescence. The UV reduction camera utilizes multilayer mirrors having high reflectivity at the UV wavelength and images the mask onto a resist coated substrate at a preselected demagnification. The mask can be formed integrally with the source as an emitting mask.

Abstract: A variable incident angle exposure apparatus wherein the incident angle of exposure light can be set as desired.

Abstract: UV-hardenable reaction resin compounds are irradiated in an applicator and immediately fed to an object that is to be covered. An initial, not activated reaction resin compound is irradiated after entering an input opening in a reactor having an irradiation space, a UV-radiation source and, optionally, a reflector. Immediately thereafter the activated compound is fed to an object to be coated or to an object to be surrounded, in an open casting mold or to a closed casting mold via the exit opening, optionally via a casting canal. The method and the apparatus are particularly well suited for covering semiconductor components and for encapsulating active and passive components as well as for cementing UV-impermeable fitting parts.

Abstract: An apparatus is disclosed for the production of oxygenated blood. The apparatus incorporates a vessel for containing the blood that is to be processed, an ultraviolet lamp and an infrared lamp being associated with the vessel. A feed pipe extends into the vessel to a position near the bottom of the vessel, such feed pipe being connected to a source of ozone. The vessel is essentially in the form of an inverted bottle, the neck opening of which is closed and the base of which incorporates a central opening for the feed pipe, the vessel and the feed pipe being designed as disposable items. The vessel is installed in the area of a working surface of the apparatus so as to be releasable therefrom, while the feed pipe is connectable to a coupling on a line that leads to the ozone source.

Abstract: Apparatus for testing and/or calibrating a detector comprising a latent image generator, the generator having differing reflectance coefficients across its surface such that in use, when irradiated by collimated radiation the output intensity from some regions is relatively high and from other regions is relatively low.

Abstract: A fluorescent lamp and system for providing cosmetic tanning. The lamp includes a first ultraviolet-emitting phosphor disposed on a portion of the circumference of the interior of an ultraviolet-transmitting glass envelope. A second ultraviolet-emitting phosphor is disposed on the remaining portion the lamp envelope. The lamp further includes bases having electrical contacts extending therefrom and lying in a plane which passes through the demarcation lines formed between the first and second ultraviolet-emitting phosphors. In one embodiment, the proportions of UVB to UVA from the same light source are about 1.6 percent and 4.2 percent. In another aspect of the invention, a suntanning system includes an external reflector positioned adjacent the fluorescent lamp. The external reflector is effective in maintaining approximately the same irradiance level in the UVA region independent of the rotational alignment of the lamp.

Abstract: A relatively large diameter, sharply focused beam of invisible light is produced by a projector (10) for the purpose of lighting up a person, object, etc. to be viewed at night. The projector (10) is used in conjunction with a night vision telescope (12) which includes a light intensifier (88). The projector (10) includes a pulsating infrared LED, or a laser diode, adapted to produce a high intensity narrow beam of invisible light. This beam of invisible light is enlarged by a projection lens assembly (26) adapted to sharply focus the light into a collimated light beam of about the diameter of the projector housing (20). The light source (30) is pulsed on and off, and is on only about 10-20% of the time. When on it is illuminated by a high level current which would quickly burn out the light (30) if operated continuously. The intermittent operation of the light (30) at high current produces a nonflickering high intensity light beam.