Abstract: A peripheral projection, display screen system including (a) a display screen having a rear side and a diagonal dimension, (b) an image-projection source coupled to a peripheral of the system and disposed at a defined, image-projection system depth rearwardly of the screen's rear side, (c) an optical path structure operatively interposed and optically coupling the source and the rear side of the screen, coupling the image from the source to the screen's rear side, and within the mentioned, defined image-projection system depth, a displayable image projected by the source, and (d) system geometry structure organizing the screen, the source, and the optical path structure, whereby the depth ratio of the diagonal dimension of the screen to the image-projection depth is equal to or more than 10:1.

Abstract: A flat projection television comprising an imagine engine mounted adjacent a top of an enclosure and optically coupled to a collimator mirror, a flat mirror, a mirror assembly comprising a plurality of cylindrical mirrors, and a diffuser screen. The image engine includes a cylindrical lens which expands an outgoing image horizontally. The image engine projects the image downward from the top of the enclosure toward the bottom of the enclosure where the horizontally expanding image encounters the collimator mirror which collimates the expanding beam bringing the horizontal lines back into parallel with one another. The collimator mirror also reflects the collimated image towards the front of the enclosure where it encounters the flat mirror oriented to deflect the image upward into the mirror box location of the enclosure at an appropriate angle.

Abstract: A projection assembly and projection method for accurately reproducing animated and live characters, objects, and effects. The projection assembly uses a high precision robotic mirror system to achieve very high levels of image resolution, brightness, and contrast. The assembly includes a projector receiving an input image stream, and a mirror assembly is positioned proximate to the projector outlet. The mirror assembly uses positionable mirrors to reflect the projected images onto a display surface at positions that define an animation pattern on the display surface for the projected image or character. The assembly includes a motor controller assembly positioning the mirrors based on position data defining the animation pattern. The projected images may be provided in a projection area that is a fraction of the size of the display surface, such that the resolution and output light of the projector are concentrated on the display surface within this projection area.

Abstract: In order to obtain effects of the increase in brightness of images, miniaturization, low cost, convenience of handling, default prevention, in inconvenience of assembly, which are can be obtained by a projection system, the projection system comprises at least one light-emitting device; a time division supplying device of light that time-divides light emitted from the at least one light-emitting device and supplies it; a first condensing lens that focuses light passing through the time division supplying device of light; a first mirror that reflects light passing through the first condensing lens; an integrator that makes light reflected from the first mirror into a planar light; a second mirror that reflects light passing through the integrator; a third mirror that reflects light reflected from the second mirror to a DMD side; and a projection lens that projects light reflected from the second mirror onto a screen and has an optic axis disposed at both sides of the second mirror and the third mirror, respect

Abstract: There is provided a light source unit which includes a luminescent light source which receives excitation light so as to emit light of a predetermined wavelength band, excitation light sources which shine excitation light on to the luminescent light source, a reflection space having the luminescent light source in an interior thereof and an emission space which emits luminescent light source light emitted from the reflection space from an emission port whose area is made smaller than the area of the luminescent light source and a projector which employs the light source unit.

Abstract: An optical beam scanning device includes a polygon mirror 80 in which tilt angles with respect to a rotation axis of the polygon mirror 80 of respective plural reflecting surfaces are set to angles corresponding to photoconductive members associated with the respective reflecting surfaces, a post-deflection optical system A1 that guides light beams reflected and deflected by the respective plural reflecting surfaces in the polygon mirror 80 to the photoconductive surfaces of the photoconductive members corresponding to the respective reflecting surfaces, and a pre-deflection optical system 7a that shapes the light from the light source to be a light beam of a predetermined sectional shape and guides the light beam to the polygon mirror 80, the pre-deflection optical system 7a guiding the light from the light source to the polygon mirror 80 through an optical path that passes, in the main scanning direction, on an optical axis of the post-deflection optical system A1 and passes, in the sub-scanning direction,

Abstract: An image projection system (100) has a laser (102, 104, 106) providing at least one beam (103, 105, 107) to a scan mirror apparatus (130) for scanning the at least one beam (103, 105, 107) in two orthogonal directions (404, 406). The scan mirror (130) includes an oscillating portion (204, 904) disposed contiguous to a frame (202) and includes a reflective portion (218, 918) capable of reflecting the beam (103, 105, 107). Circuitry (500) is provided for measuring the capacitance between interdigitated teeth (212, 214, 912, 914) on the frame (202) and the oscillating portion (204, 904).

Abstract: An imaging system (200) includes a plurality of laser sources (201) configured to produce a plurality of light beams (204). One or more optical alignment devices (220) orient the light beams (204) into a collimated light beam (205). A light modulator (203) modulates the collimated light beam (205) such that images (206) can be presented on a display surface (207). Speckle is reduced with an optical feedback device (221) that causes the laser sources (201) to operate in a coherence collapsed state. Examples of optical feedback devices (221) include partially reflective mirrors and beam splitter-mirror combinations.

Abstract: Prism elements having TIR surfaces placed in close proximity to the active area of a SLM device to separate unwanted off-state and/or flat-state light from the projection ON-light bundle. The TIR critical angle of these prisms is selected to affect either the off-state light or additionally, any portion of flat-state light reflected from the SLM. These TIR surfaces limit the contamination of light along the projection path, which tends to degrade the system contrast. To further improve the optical performance of the system, these TIR prisms can be attached directly to the SLM package, completely eliminating the package window.

Abstract: An optical system includes a light source array, a dichroic mirror set, a light converting device and a light guide pipe. The light source array is used for emitting a first homogeneous light. The dichroic mirror set is disposed in a light path of the first homogeneous light and used for reflecting a part of the first homogeneous light to the light guide pipe, transmitting the remaining part of the first homogeneous light to the converting device. The light converting device is disposed in the transmitting light path of the dichroic mirror and used for transferring the first homogeneous light into a second, third homogeneous light. The dichroic mirror is further used for reflecting the second, third homogeneous light to the light guide pipe. The light guide pipe is used for mixing the first, second and third homogeneous light to obtain a white light.

Abstract: A projection optical system including a projection lens, a first mirror that reflects a light from the projection lens, and a second mirror that widens an angle of a light from the first mirror by reflecting the light projects a light modulated according to an image signal from an optical engine unit. A third mirror reflects a light from the projection optical system. A screen transmits a light from the third mirror. An optical axis of the projection lens substantially matches an optical axis of the second mirror, and the light from the optical engine unit is shifted to a specific side from the optical axis of the projection lens.

Abstract: Provided is a projector which includes a first lamp, a second lamp in an identical direction to the first lamp, a projection optical system that emits image light to an outside, a first mirror that reflects the light from the first lamp or the second lamp to cause the light to enter the lighting optical system, a movable mirror that, when the first lamp is turned on, causes the light to directly enter the first mirror by deviating from an optical path connecting the first lamp and the first mirror and, when the second lamp is turned on, reflects the light by being set up on the optical path to cause the light to enter the first mirror, and a second mirror that reflects the light from the second lamp to cause the light to enter the movable mirror.

Abstract: A waveguide 60 formed of material 62 allows propagation of image bearing light along a light pathway 64 by total internal reflection of the image bearing light. The layer of material 62 is a light transparent material arranged to allow an observer, not illustrated, to look through the layer of material 62 whilst also arranged to carry image bearing light. A grating element 66 carried within the layer of material 62 is arranged such that impinging image bearing light following the light pathway 64 is either diffracted out of the layer of material 62 as a pupil of image bearing light 68a to 68n or is reflected by either surface 70 or surface 72. The efficiency of the grating element 66 is varied along the length of the layer of material 62 to achieve the desired pupils of image bearing light 68a to 68n along the length of the layer of material 62. This results in a more even brightness of pupils of image bearing light 68a to 68n, as perceived by the observer looking through the layer of material 62.

Abstract: Light emitted from a lamp enters a color wheel having a region for allowing a predetermined color to pass therethrough, is reflected on a mirror, and enters a DMD. After this, the light is reflected by the DMD and enters a color sensor, which then detects the color of the transmitting light. A projection apparatus automatically synchronizes the control on the rotation of the color wheel and the control on the proceeding direction of the transmitting light by the DMD, based on a color time-division pattern of the transmitting light detected by the color sensor.

Abstract: A lightweight, compact image projection module, especially for mounting in a housing having a light-transmissive window, is operative for sweeping a composite laser beam as a pattern of linear scan lines on a planar projection surface and for causing selected pixels arranged along each linear scan line to be illuminated to produce an image of high quality and in color.

Abstract: A system and method for uniform light generation in projection display systems. An illumination source comprises a light source to produce colored light, and a scrolling optics unit optically coupled to the light source, the scrolling optics unit configured to create lines of colored light from the colored light, and to scroll the lines of colored light along a direction orthogonal to a light path of the illumination source. The scrolling optics unit comprises a single light shaping diffuser to transform the colored light into the lines of colored light, an optical filter positioned in the light path after the light shaping diffuser, and a scrolling optics element positioned in the light path after the optical filter. The single light shaping diffuser is capable of simultaneously transforming colored light into lines of colored light having substantially uniform intensity to provide uniform illumination.

Abstract: In accordance with one embodiment of the present disclosure, a system comprises a projection system. The system further includes an image generator disposed in the projection system. The image generator is operable to generate a plurality of rays. The system further includes an objective lens disposed in the projection system. The objective lens is operable to refract the plurality of rays. The system further includes a component operable to reflect the refracted rays onto a target in order to form an image. The image is operable to be moved in relation to the target. The movement of the image is independent of any displacement of the projection system in relation to the target.

Abstract: A micro-mirror based projection display system in an enclosure with minimum chin and depth measurements is disclosed. A light source, such as a solid state laser light source, generates light of multiple primary colors that is modulated by a digital micro-mirror device. The projection optics of the system include a telecentric rear group of glass lenses with spherical surfaces, followed by a pair of aspheric lenses formed of plastic. A folding mirror, such as a single-piece or multi-piece angular mirror, is disposed between the aspheric lenses, to reduce the depth of the enclosure, and an aspheric mirror projects the image onto a TIR Fresnel projection screen. The aspheric lenses are magnifying to reduce the magnification required of the aspheric mirror, and the aspheric lenses and mirror are clipped to reduce enclosure volume. A folding mirror may be used after the aspheric mirror to further reduce the depth of the enclosure.

Abstract: A projection type display apparatus is provided that is safe even when a person looks directly into a laser beam. A laser operation control unit sets the output power of at least one laser source so that intensity A (mW/mm2) of the laser beam on at least one spatial light modulation element satisfies relationship of A<686×B2 when numerical aperture B on image side of an illumination optics system is set.

Abstract: An arc tube includes: a tube spherical portion containing a pair of electrodes each of which has a shaft portion and a coil winding portion formed by winding coil around the shaft portion; and a pair of seal portions extending from both sides of the tube spherical portion. The coil winding portion of at least one of the electrodes has a coil portion formed by winding the coil at least once around the shaft portion in the longitudinal direction of the shaft portion, a tip disposed on the tip side of the coil portion, and a base disposed on the base side of the coil portion. The coil of the base positioned on the surface side of the electrode is melt-treated. The coil forming the base is not melted to be combined with the shaft portion.

Abstract: A displaying method of a digital light processing (DLP) projector includes the steps of: providing a light modulation device including a driver printed circuit board and a digital micromirror device (DMD), wherein the DMD includes a plurality of micromirrors each having a first stable state and a second stable state, and a predetermined light incident direction, the DMD is installed on the driver printed circuit board; providing an illumination light beam being incident on the DMD along an operating direction different from the predetermined light incident direction, modulating the illumination light beam to an imaging light beam by the DMD and directing the imaging light beam to a projection lens for projecting an image. A DLP projector made thereby has a relatively lower manufacturing cost.

Abstract: A digital image projector includes a light assembly configured to project light along a light path from at least one laser array light source, the projected light having an overlapping far field illumination in a far field illumination portion of the light path; a temporally varying optical phase shifting device configured to be in the light path; an optical integrator configured to be in the light path; a spatial light modulator located downstream of the temporally varying optical phase shifting device and the optical integrator in the light path, the spatial light modulator configured to be located in the far field illumination portion of the light path; and projection optics located downstream of the spatial light modulator in the light path, the projection optics configured to direct substantially speckle free light from the spatial light modulator toward a display surface.

Abstract: A multiple path stereoscopic projection system is disclosed. The system comprises a polarizing splitting element configured to receive image light energy and split the image light energy received into a primary path and a secondary path, a reflector in the secondary path, and a polarization modulator or polarization modulator arrangement positioned in the primary path and configured to modulate the primary path of light energy. A polarization modulator may be included within the secondary path, a retarder may be used, and optional devices that may be successfully employed in the system include elements to substantially optically superimpose light energy transmission between paths and cleanup polarizers. The projection system can enhance the brightness of stereoscopic images perceived by a viewer. Static polarizer dual projection implementations free of polarization modulators are also provided.

Abstract: A digital micromirror projection display system is disclosed in which “off” pixel light is recaptured and recycled. In the disclosed system, a digital micromirror device directs incident light for “on” pixels in the image to be displayed through projection lenses to a projection screen. The digital micromirror device directs incident light for “off” pixels back toward the light source for recapture by a light integrator. Both the incident and projected light can pass through a rear group of projection lenses, with the first projection lens being disposed near the digital micromirror device. A mirror directs the incident light toward the digital micromirror device, and the “off” pixel light from the digital micromirror device toward the light integrator. As a result, “off” pixel light can be recycled without degrading image contrast, in a manner that can place fast projection lenses close to the digital micromirror device to save cost.

Abstract: A light source device includes a discharge lamp and a reflection mirror having a plurality of concave curved surfaces. Each of the plurality of concave curved surfaces is an ellipsoidal surface. A first focal point of each of the ellipsoidal surfaces is disposed at the light emitting center of the discharge lamp. A second focal point of each of the ellipsoidal surfaces is disposed, when viewed from a predetermined first direction perpendicular to a system optical axis passing through the light emitting center, on the opposite side of the system optical axis to the ellipsoidal surface, and when viewed from a second direction perpendicular to the system optical axis and the first direction, on the side where the ellipsoidal surface is present with reference to the system optical axis.

Abstract: A projection optical system includes: a refracting optical section composed mainly of a plurality of lenses disposed in order from a reducing side, and having positive power; a first reflecting optical section having a concave reflecting optical surface; and a second reflecting optical section having a convex reflecting optical surface, wherein the projection optical system satisfies the following conditional expression, denoting a focal length of a total system combining the refracting optical section, the first reflecting optical section, and the second reflecting optical section as F, and a focal length of the refracting optical section as FL: 0.2<F/FL<0.5??(1).

Abstract: A projection optical system including a first optical system configured to form a second image conjugate to a first image and a second optical system configured to include a reflective optical element which reflects light from the second image and to project a third image conjugate to the second image onto a projection surface is provided, wherein the first optical system has a Petzval sum with a sign opposite to a sign of a Petzval sum of the second optical system.

Abstract: A projection device embodiment comprises a light source system, a gate with a cross sectional gate area, and projection optics. The light source system includes a solid-state light source configured to provide light, and light source optics. The light source optics are configured to distribute light from the solid-state light source across the gate area of the gate. The gate is configured to be used to produce an object to be imaged by the projection device. The projection optics is configured to project an image of the object.

Abstract: A display system includes a coherent light source that can emit a coherent light beam, an optical component that can direct the coherent light beam to a spatial light modulator, a transport mechanism that can move the optical component to produce a movement in the coherent light beam, and a spatial light modulator having a two-dimensional array of mirrors each configured to selectively reflect the coherent light beam either toward a screen surface or away from the screen surface to form a display pixel on the screen surface. A display image is formed on the display screen by display pixels produced by the mirrors that reflect the coherent light beam toward the screen surface.

Abstract: A projection optical system for use in an image projection apparatus illuminating a lightbulb forming an image in accordance with a modulating signal with illumination light from a light source is disclosed. The projection optical system includes first and second optical systems arranged along an optical path defining an upstream-downstream direction in the order described from upstream to downstream on the downstream side of the lightbulb. The first optical system includes at least one dioptric system and has positive power. The second optical system includes at least one reflecting surface having power and has positive power. The image formed by the lightbulb is formed as an intermediate image in the optical path, and the intermediate image is magnified and projected.

Abstract: Provided is a laser display device. The laser display device may include at least one light source configured to emit at least one laser beam, at least one scanning unit configured to perform a scanning with the at least one laser beam, and an image forming unit configured to generate excitation light and scattering light by receiving the at least one laser beam from the scanning unit to form an image.

Abstract: A mobile terminal including: a main body having a wireless communication module; and a projector mounted at the main body and projecting beams to display an image on an image display region separated from the main body, wherein when an operation mode is being executed while the image is being displayed, the projector displays a notification message indicating the executed operation mode on the image display region. If the operation mode is executed while an image is being displayed by means of the projector, the corresponding information is displayed on the image display region, to thus effectively transfer the information about the execution of the operation mode to the user.

Abstract: A projector includes: a light source that emits light having an asymmetric illuminance distribution; a light modulation device that modulates the light emitted from the light source; and an optical member disposed in an optical path between the light source and the light modulation device, the optical member changing the illuminance distribution of the light from the light source, wherein the optical member changes the illuminance distribution of the light passing therethrough in such a way that a highest illuminance area in the illuminance distribution of the light after passing through the optical member is shifted toward the center of the optical member as compared with the position of the highest illuminance area in the illuminance distribution of the light before incident on the optical member.

Abstract: A light source device includes: an arc tube; a first reflection mirror which surrounds a part of the entire circumference of the arc tube around an optical axis; and a second reflection mirror disposed oppositely to the first reflection mirror, wherein the curvature at the cross point of a fourth plane extending in parallel with a plane extending perpendicular to the optical axis and containing the light emission area and the cross-sectional shape on a third plane passing through the light emission area, extending in parallel with the optical axis, and crossing a first plane passing through a light emission area and extending in parallel with the optical axis in the first reflection mirror is larger than the curvature at the cross point of the fourth plane and the cross-sectional shape on the first plane in the first reflection mirror.

Abstract: A projection optical system that receives light from a display element to project an image displayed by the display element onto a screen with enlargement at a varying magnification achieved by varying the projection distance to the screen has: a refractive optical system composed of one or more refractive lenses and having a positive optical power; and a concave-surfaced mirror disposed to the screen side of the refractive optical system and having a plane-symmetric reflective surface. The projection optical system includes at least one optical element designed to be movable for focusing. The projection optical system forms an intermediate image between the refractive optical system and the concave-surfaced mirror. Moreover, a prescribed conditional formula is fulfilled.

Abstract: In a projection optical system for use in an image projection apparatus illuminating an image display panel forming an image in accordance with a modulating signal with illumination light from a light source, the projection optical system includes first and second optical systems arranged along an optical path defining an upstream-downstream direction in the order described from upstream to downstream on the downstream side of the image display panel. The first optical system includes at least one dioptric system and has positive power. The second optical system includes at least one reflecting surface having power and has positive power. The image formed by the image display panel is formed as an intermediate image in the optical path, and the intermediate image is magnified and projected.

Abstract: An optical system (light guiding optical system) for guiding G-light and R-light to liquid crystal panels is protruded in an opposite direction from projection optical system with regard to an optical axis of a light source. A space is created between an optical engine and a wall surface, and air stream for suction fan is thus secured. A distance (H1) between the optical engine and the wall surface can be reduced to, for example, a thickness of an external housing of the projector. Since a unit comprising the light source and a suction fan is retracted in a direction of the projection optical system than a protruded portion of the light guiding optical system, a distance (H2) from an end edge of the optical engine to a projection light emitting position can be reduced.

Abstract: In one embodiment, a method includes transmitting one or more light beams by a first portion of a light modulator formed outwardly from a substrate. The one or more transmitted light beams are spatially integrated. A second portion of the light modulator is formed outwardly from the substrate. The second portion of the light modulator spatially integrates the transmitted light beams.

Abstract: To reduce the color break-up and to provide high quality projection images. A method of driving a spatial light modulator, including generating a sub-frame pulse signal for a first colored light R1 through R8, B1 through B8, generating a sub-frame pulse signal for a second colored light G1 through G8, arranging the sub-frame pulse signals for the respective colored light so that at least three of the sub-frame pulse signals for the first colored light R1 through R8, B1 through B8 adjoin either one of the sub-frame pulse signals for the second colored light G1 through G8 during at least one frame of the image, and driving a plurality of movable mirror elements in accordance with the sub-frame pulse signals for the respective colored light arranged in arranging the sub-frame pulse signals, the movable mirror elements being alternatively moved at least to a first reflecting position and a second reflecting position.

Abstract: Disclosed herein is an image projecting apparatus, including: a one-dimension type light modulating device for modulating a light in accordance with image information; a projection optical system; and a light deflecting device for deflecting an image light in a direction approximately perpendicular to an extension direction of a one-dimensional image light emitted from the one-dimensional light modulating device; wherein the light deflecting device is composed of a first light deflecting device arranged between the projection optical system and the one-dimension type light modulating device, and a second light deflecting device arranged on an emission side of the projection optical system; the second light deflecting device is detachably mounted.

Abstract: A projection display device includes: an optical engine that emits image light in a direction parallel to a projection plane; a first reflective optical system that reflects the image light in a first direction away from the projection plane; a second reflective optical system that reflects the image light reflected by the first reflective optical system in a second direction away from the optical engine and closer to the projection plane; and a refractive optical system. The refractive optical system is divided into a first refractive optical system interposed between the optical engine and first reflective optical system, and second refractive optical system interposed between the first and second reflective optical system. The optical engine is arranged so that a mounting plane of optical components is almost perpendicular to a plane parallel to both of the first and second directions and is almost parallel to the projection plane.

Abstract: A projector includes: a light emitting device; a light modulation device adapted to modulate a light beam emitted from the light emitting device in accordance with image information; and a projection device adapted to project the image formed by the light modulation device, wherein the light emitting device includes a light emitting element formed of a super luminescent diode, and adapted to emit light when flowing current through an active layer sandwiched between a first cladding layer and a second cladding layer, and a base supporting the light emitting element, and provided with a first reflecting surface and a second reflecting surface each adapted to reflect the light emitted from the light emitting element, the light emitting element has a configuration of emitting the light from a first end surface and a second end surface, a direction of first outgoing light emitted from the first end surface of the light emitting element and a direction of second outgoing light emitted from the second end surface of

Abstract: Diffractive patterns are disposed on a MEMS substrate in the gaps between the MEMS micromirrors to reduce backreflection of light leaking through the gaps and reflected by the MEMS substrate. The diffractive patterns are silicon surface-relief diffraction gratings or silicon oxide gratings on silicon substrate. Sub-wavelength gratings are used to suppress higher orders of diffraction; 50% duty cycle surface relief gratings on a substrate having index of refraction close to 3 are used to suppress both reflected and transmitted zero orders of diffraction simultaneously. The gratings have lines running parallel or at a slight angle to the gaps, to prevent the diffracted light from re-entering the gaps.

Abstract: A light collector is provided to converge light from a light source down to a range of acceptance angles of an illumination optic, and to couple the converged light into the illumination optic, where the range of acceptance angles of the illumination optic is less than a range of emission angles of the light source.

Abstract: A liquid crystal rear projector device of the present invention includes a lamp unit providing a light source, a cooling fan for cooling the lamp unit, and an optical system for generating color image light with the lamp unit providing a light source, the lamp unit including a light emitting tube providing a light source, and a reflector for reflecting light emitted from the light emitting tube toward the optical system. The reflector has an air introduction hole for introducing air discharged from the cooling fan into the reflector, which is provided near the spherical portion of the light emitting tube, and faces to a vertical top of the spherical portion to blow the air to the top.

Abstract: In a projection type display apparatus for enabling to display an image, by projecting an image on an image display element(s), enlargedly, upon a nearly horizontal surface, such as, a table, a reflection mirror for reflecting a light from a light source is so disposed that an optical axis of the light source is nearly perpendicular to an optical axis of a lens group having a plural number of lens elements, which are disposed symmetric with respect to the optical axis.

Abstract: First and second reflectors are provided. The first reflector has a function of reflecting a light ray emitted from a light source and directing it toward an image display element and the second reflector has a function of changing the direction of a light ray so as to be reflected by the first reflector which light ray is emitted from the light source and not reflected by the first reflector. An outer periphery shape of the second reflector is changed correspondingly to an effective area of a first array lens 10.

Abstract: A reflector for the lighting device and an illumination system of the projection apparatus are provided. The reflector comprises a first reflecting structure and a second reflecting structure disposed on the portion of the first reflecting structure. The reflecting surfaces of the first and second reflecting structures are formed with a distance therebetween. After the first portion of the light is reflected from the first reflecting surface and the second portion of the light is reflected from the second reflecting surface, the second portion of the light is adapted to remove the centrally dimmed area at the opening of the lighting device. Thus, the luminance performance can be improved.

Abstract: A reflective mirror manufacturing method for manufacturing a reflective mirror used in an illumination device including an arc tube including a light-emitting portion and a reflective mirror including a reflective surface that reflects light from the light-emitting portion in a predetermined direction, includes: a first step of forming a tube by heating a tube including a material of the reflective mirror, thereafter putting the tube in a form block, applying internal pressure with an inert gas to cause a center portion of the tube to expand, so that part of an inner surface of the expanded center portion includes a shape corresponding to the reflective surface of the reflective mirror; a second step of cutting the tube at the center portion to form a reflective mirror member; and a third step of forming a reflective layer on an inner surface of the reflective mirror member.

Abstract: An image projection system includes a light source for generating a light beam, a reflective housing, and an invisible-light reflector. The reflective housing includes an opening and forms an accommodating space for accommodating the light source so that the light beam can emit from the opening along an optical path. The invisible-light reflector, whose normal is arranged to form an acute angle with the optical path, is installed at a reflecting position intersecting with the optical path outside the opening of the reflective housing. The invisible light of the light beam will be reflected back to the accommodating space by the invisible-light reflector without any destruction caused by the invisible light.