Abstract: A method for improving the resolution and contrast of images associated with coherent recording is presented, which includes conventional reconstruction with a reference wave followed by re-imaging the intermediately formed image through a system based on techniques from confocal microscopy. This method provides the opportunity to bring the benefits of the optical confocal microscope, namely resolution, contrast improvement, and the accompanying three-dimensional visualization, to such diverse imaging regimes as infrared, X-ray, ultraviolet, as well as other wave propagation systems such as seismic, sonar and ultrasound imaging. In addition, through snap-shot acquisition of said coherent recordings, the capability of time resolution may be added, thus adding functionality in wavelength regions where the confocal microscope currently operates.

Abstract: A color holographic head up display which can be mounted on, for example, an airplane or automobile for projecting a color image displayed on a screen. The color holographic head up display in accordance with the present invention comprises an information display comprising a 2-dimensional array of pixels for displaying information to be projected, a relay optical system for relaying an image displayed on the information display, and a holographic combiner having holographic optical elements whose number is the same as the number of the pixels of the information display for delivering the image from the relay optical system to the viewing zone of the human eye, the holographic optical elements being arranged to correspond to the pixels of the information display. According to the present invention, the surrounding scenery and navigation information of a color image are simultaneously projected without noise due to intermodulation, and a high diffraction efficiency can be achieved.

Abstract: A system for supporting a fire fighting for a building and a fire fighting method using the same which are capable of more effectively performing a fire fighting operation by providing, in real time.

Abstract: A second supporting section installed detachably on a supporting surface is connected to a first supporting section installed detachably on a head-up display, such that the supporting sections can move relative to each other. Receiving sections provided on the under side of the head-up display comprises receiving surface. The receiving surface faces the under side of the head-up display via a gap. The first supporting section comprises a inserting section. The inserting section is forced removably along the under side of the head-up display into the gap between the receiving surface and the under side of the head-up display. By means of the force fit of the inserting section into the gap, the under side of the head-up display engages with the upper surface of the first supporting section.

Abstract: The intensified visual display relates to visual displays which combine generated images with the view of the environment surrounding a user and transmit such combined visual information to the eye position of the user. A fold mirror (1) frequently utilized in such displays reflects only a fraction of the light striking it and, similarly, transmits only a different fraction of the light reaching it. The fold mirror (1) will reflect a maximum amount of light when such light is S polarized and transmit a maximum amount of light when the light is P polarized. If the image generator produces S polarized light, one quarter-wave plate (3) is used to assure that image light to be reflected by the fold mirror (1) is S polarized while image light to be transmitted through the fold mirror (1) is P polarized. If the image generator produces P polarized light, a first quarter-wave plate (31) and a second quarter-wave plate (32) are employed.

Abstract: A plurality of hologram elements are simultaneously exposed to a constructing light while they are arranged in the form of a stack, so that the incident beam can be uniform within the exposure area. The plurality of hologram elements should be transparent to the constructing light.

Abstract: A head up display unit equipped at least with transparent and flat image information display means, transparent and flat light irradiating means arranged in an opposed and close contact relationship with the image information display means, light supply means for supplying light to the light irradiating means, image-display control means for controlling image display, and light-supply control means for controlling light supply. The display unit is a compact head up display unit which can be used in any place in the interior of an automobile.

Abstract: A low cost, compact projection display source that serves as a very bright image source for an automotive head up display. The present invention is comprised of a high intensity halogen light source and a liquid crystal display. The liquid crystal display is controlled by display electronics that write images onto the liquid crystal display that are to be displayed to the driver or passengers of a vehicle. Light output from the high intensity light source is transmitted through a piece of infrared energy absorbing glass, a decentered lens, such as a Fresnel lens, and a diffuser that uniformly backlights the liquid crystal display. Crossed polarizers are used on either side of the liquid crystal display. The high intensity light output transmitted by the liquid crystal display is passed through a yellow-orange output window which is projected onto a toric combiner for display to the driver of the vehicle.

Abstract: As a combiner, a hologram prepared by exposure to light is used wherein a combination of the central wavelength .lambda., the halfwidth .DELTA..lambda. and the diffraction efficiency .eta. of the diffraction spectrum of light minimizes the color difference between the color tone of light from a light source and the color tone in average of reflection light by the combiner, when observed by changing the angle, or the sum of the square of the color differences between the color tone of the light from the light source when observed by changing the angle and the color tone of the reflection light by the combiner.

Abstract: A display system for a binocular helmet visor having image projectors projecting images on a semi-reflecting internal wall of the visor of the helmet. One image faces the right eye and another image faces the left eye. The shape of the surface of the internal wall of the visor makes it desirable to cross the optical paths of the two projectors at the helmet wearer's forehead in order to limit the deformation of the images. The optical paths of the two projectors are folded with holographic mirrors in a manner which results in a compact structure, reducing the space required for the visor and the overall weight of the helmet.

Abstract: Detachable hologram assembly for a compact holographic sight includes a hologram of a reticle image or other desired alignment indicia mounted within a resilient, detachable frame. The frame includes a pair of generally planar, non-parallel registration surfaces and an aperture extending through the frame at the junction of the registration surfaces. A hologram mount, also including a pair of registration surfaces which are complimentary to those of the frame is affixed to, or integral with, the sight. A fastener secures the hologram assembly to the mount with a force sufficient to maintain the registration surfaces of the frame in frictional fit, respectively, with the corresponding registration surfaces of the mount.

Abstract: This specification discloses a displaying apparatus having a display emitting light, and an optical element formed by two holograms each having optical power and partially overlapping each other. The light from the display is diffracted by one of the holograms to be directed to an observer's left pupil, and is diffracted by the other hologram to be directed to the observer's right pupil.

Abstract: The sight comprises a support adapted for mounting onto an instrument to be aimed at a target, an optical device mounted onto the support for creating an image including a first sighting mark at a first finite distance with respect to the optical device, and a device mounted on to the support for providing a second sighting mark at a finite distance with respect to the first sighting mark. The instrument is aimed at the target by aligning the sighting marks. Since at least the first sighting mark is an image, its position can be chosen to improve the accuracy of aiming by alignment of the marks without having to physically accommodate the first mark.

Abstract: A method of producing a holographic optical element which is capable of imparting complex corrections to the holographic optical element and of effecting the exposure using a short optical path permitting little disturbance to be infiltrated. A correction holographic optical element 13 for correcting the characteristics of the holographic optical element is disposed in at least one of the optical paths of an object beam 35 and a reference beam 36 that fall on a photosensitive material 11. The object beam 35 may be one obtained by reflecting the reference beam 36 by a reflection-type holographic optical element such as a reflection-type master holographic optical element 12. In the case of a holographic optical element used for the head-up display, the correction holographic optical element 13 may be given characteristics for correcting the curvature of the windshield or characteristics for correcting color aberration.

Abstract: A holographic stoplight system that includes a stoplight hologram (21, 21') supported adjacent the inside surface of a rear window (211) of a vehicle, and a light source (29, 31) for providing a converging beam that is vertically converging and predominantly horizontally colimated. The stoplight hologram is illuminated with the vertically converging beam, or with a predominantly collimated beam provided by a collimating lens (27) that collimates the vertically converging beam.

Abstract: For displaying moving images on a head mounted, temporal modulation display device from a video source, without image break-up appearing in the observed image, an image shift device is provided for shifting each temporally separated component image within each display cycle of grey scale component images representing each frame of the video source. The display device is for use with head mounted displays in which an LCD or other FPD using temporal modulation is used to display video images without image break-up during head motion.

Abstract: A biocular display system (19) for generating a virtual image (30) of a visible display (20). A diffractive binary optical element (22) is used to create the virtual image (30). The binary optical element (22) contains magnifying power to increase the size of the virtual image (30). Also, the binary optical element (22) contains prismatic power to displace the virtual image (30) away from the display (20). Multiple displays (40), (42) may be viewed by employing a binary optical element (34) having multiple diffractive orders.

Abstract: A heads-up display unit provided with a display device serving as display image forming means which displays a display image. A hologram serves as a reflecting means, and reflects the display light emitted from the display device, causing reflection of the display image on the interior surface of a vehicle's windshield. A display image is formed outside the windshield towards the front of the vehicle. A concave mirror having a different focal length in different directions is recorded in the hologram serving as a reflecting means so as to offset distortion of the display image caused by curvatures of the windshield. This construction makes it possible to cause the windshield to display a display image free from distortion.

Abstract: A wide view angle display apparatus includes a pair of display devices each including a display for displaying an image, a high resolution display for superimposing a high resolution image at a center portion of the displayed image and eye movement detection means for ascertaining the view point of the user's eye, a support/drive means associated with each display device for supporting the display device and moving it in accordance with a signal from the eye movement detection means to keep the center of the displayed image coincident with the view point, a video signal generating means associated with each display devices for sending a view point video signal to the display based on a signal from the eye movement detection means, and a high resolution video signal generating means associated with each display device for sending a high resolution video signal to the high resolution display.

Abstract: A device for putting away a holographic mirror includes at least one curved slideway, a carriage for moving on the slideway from an operational position to a position where the mirror is put away, the carriage being fixedly joined to the mirror, and a holder holding the mirror in a position where it is put away. The device is used for stowing of a holographic mirror in an aircraft.

Abstract: A holographic thin rear exterior lamp for a vehicle including a light pipe (11) having first and second opposing surfaces (11a, 11b), a rear exterior lamp hologram (13, 113) attached to one of the first and second surfaces of the light pipe, a polarization rotating retarder film (16, 116) attached to one of the first and second opposing surfaces oppositely from the rear exterior lamp hologram, a light source (17, 19) for providing a substantially collimated beam, a transmission hologram (15) disposed on one of the first and second surfaces of the light pipe for coupling the substantially collimated beam into the light pipe such that a portion of the substantially collimated light propagates by total internal reflection within the light pipe, the rear exterior lamp hologram and the polarization rotating retarder film. The polarization rotating retarder film is configured to impart a substantially halfwave retardance to internally reflected light that passes twice therethrough.

Abstract: An optical system is provided that produces bright, high contrast head-up display images which are not adversely affected by the direct exposure to sunlight of the system's virtual image source. The optical system comprises a light source system which projects a focused light beam to a segmented, electronically-addressed polymer-dispersed liquid crystal ("PDLC")-type film, which serves as a primary image source. Selected segments of the image source are made transmissive while other selected segments scatter light. Accordingly, the portions of the focused light beam incident to transmissive segments are transmitted to form a real image, while the balance of the focused light beam is scattered. A stray light-blocking means, such as a lens/aperture combination, is employed to block the scattered light. The real image is projected onto an unsegmented, electronically-addressed PDLC-type film serving as an image screen.

Abstract: A heads-up display device for a vehicle including a holographic projection optical system constituted by a transmissive holographic optical element and a holographic combiner constituted by a reflective holographic optical element, capable of reducing the number of constituting elements thereof and, thus, the total volume thereof. With the reduced volume, the holographic projection optical system is rotatable totally by use of a drive motor. By virtue of the rotatable construction of the holographic projection optical system, a driver can adjust properly the position of a reflected image indicative of various information projected onto the windshield of the vehicle, depending on the position of his eyes. A position sensor is provided for sensing the rotation of the holographic projection optical system beyond a predetermined range corresponding to a variation range of the position of driver's eyes.

Abstract: In an optical pickup apparatus, a laser beam emitted from a semiconductor laser device is reflected upward by a reflecting member, transmitted through a transmission type diffraction grating and split into at least three beams, and which beams are transmitted through a transmission type holographic optical element and condensed onto an optical recording medium by a condenser portion. A return beam reflected by the optical recording medium passes through the condenser portion and diffracted not to impinge upon the transmission type diffraction grating by the holographic optical element and directed to a photodetector portion of a light receiving device. The semiconductor laser device and the light receiving device are disposed in a mount member.

Abstract: A hologram element includes an optically transparent base plate having first and second opposite surfaces. A film of a diffraction grating is provided on the first surface of the base plate. A nonreflective member is provided on the second surface of the base plate via a dipping process. The nonreflective member includes one of a film including SiO.sub.2 particles and a film of MgF.sub.2. It is preferable that the SiO.sub.2 particles have diameters of 10-150 nm. The diffraction grating film includes, for example, one of a gelatine film, a photopolymer film, and a photoresist film. The base plate includes, for example, a flexible resin film. It is preferable that the flexible resin film is made of a material selected from the group consisting of amorphous polyolefine, polycarbonate (PC), polymethyl methacrylate (PMMA), and perfluoroalkoxypolyethylene (PFA).

Abstract: Apparatus comprising a decal disposed on an interior surface of a window and a light source for projecting light onto the to display an image outside of the vehicle. The decal comprises a protective layer having a hologram layer disposed thereon that is designed to transmit a holographic image in a predetermined viewing direction. An opaque and clear mask layer into which an icon is incorporated may be secured to the hologram layer to provide a two-dimensional image. The hologram layer is illuminated by sunlight, skylight, or a light source and projects an image to a viewer at a predefined direction. During the day, the icon is viewable because light transmits through the clear portions of the mask layer is clear, and is blocked by opaque portions of the mask layer that define the icon. At night, the decal is illuminated by light from a light source 18, or an exterior or ambient light source to produce an image viewable by the observer.

Abstract: A video image tracking system is provided for determining the orientation of an operator with respect to a simulator display. The operator carries an observation device for watching the simulator display which has a detectable object disposed therein. The video image tracking system further includes a device for locating the detectable object within the simulator display and communicates this location to a virtual reality system which displays the proper orientation and location of the virtual environment with respect to the operator. The video image tracking system is incorporated into a virtual environment deployable simulator which has an environment system for including virtual reality effects into a plurality of color keys contained within the simulator display.

Abstract: A head-mounted image display comprising a housing for covering both the eyes of the user, a support for mounting the housing on the head of the user, an image light emitting unit provided at a predetermined position in the housing for emitting image light, a pair of right and left convex lenses provided at both the eyes in the housing for enlarging the image produced by the image light emitting means, and an optical system provided within the housing for guiding the image appearing on the image light emitting unit to the pair of right and left convex lenses.

Abstract: A head-up display includes a projector which projects an image light and a hologram lens which diffracts and reflects the projected image and form a virtual image located ahead of a windshield. The hologram lens has a vertical diffraction characteristic which is equivalent to a hyperbolic or parabolic-curve mirror along a line formed by the intersection of the hologram lens and a vertical plane which includes an axis of the image light and a horizontal diffraction characteristic which is equivalent to a parabolic or elliptic curve mirror along a line which is formed by the intersection of the hologram lens and a horizontal plane which includes the axis of the image light. When the hologram is directly attached on a curved windshield which has a focal length fs (in case it is a mirror), the focal length fo of the hologram and the former focal length fs has the following relationship; 1/fo=1/fh+1/fs, where fh is a focal point when the hologram is flat.

Abstract: A hologram fitted to a rear window glass is irradiated with light from a regenerative light source to produce a holographic image to ensure the effective operation of a high mount stop lamp and to simultaneously prevent light from dazzling the driver of a following vehicle. The high mount stop lamp is provided with a hologram disposed on the inside surface of a rear automotive window glass, and a regenerative light source for regenerating the holographic image by irradiating the hologram. Part of the regenerative light source is buried in a recess in a rear parcel shelf of the automobile. A shielding wall is fitted to a part of the periphery of the regenerative light source so as, together with the rear window glass, to surround the regenerative light source to shield the light directed to the front of the automobile. The shielding wall is formed, for example, by folding up part of the decorative panel of the rear parcel shelf in the form of a wall.

Abstract: A holographic viewing apparatus for allowing an operator of a bus to view a portion of a blind spot region located in front of the bus and below the windshield of the bus. The holographic viewing apparatus includes a volume transmission holographic grating attached to a lower edge of the windshield of the bus for transmissively diffracting light from a portion of the blind spot region such that an operator of the bus sees an image of the portion of the blind spot region superimposed on a scene that is directly and non-diffractingly observed through the holographic transmission grating.

Abstract: A display device is achieved using a simplified optical system which generates an expanded exit pupil without compromising magnification or resolution. Modulated light from a source is converged toward a focal point by an optics subsystem. A scanning subsystem deflects the converging light, and thus the focal point, along a raster pattern to define a curved intermediate image plane. An exit pupil expanding apparatus defines a curved surface which coincides with the curved image plane. Impinging light rays at a given instant in time span a given incidence angle. Exiting light rays span a larger angle. As a result, the exiting light spans a larger surface area of an ensuing eyepiece. In turn an expanded exit pupil occurs beyond the eyepiece. Embodiments of the expanding apparatus include a curved diffractive optical element, fiber optic face plate, lens array and diffuser. The diffractive optical element generates multiple exit pupils, while the other embodiments generate enlarged exit pupils.

Abstract: A combiner for combining light traveling on two optical paths to permit coincident viewing of the light includes a light-transmissive substrate having first and second surfaces, the first surface having a first diffractive structure that is a computer-generated hologram formed thereon configured to correct aberrations in light travelling on the first optical path which may be incident on the first surface and a partially reflective coating on the first diffractive structure, the partially reflective coating being reflective in a narrow bandwidth only, the first diffractive structure and the partially reflective coating configured to provide corrected reflection to light travelling on the first optical path, the second surface having a second diffractive structure that is a computer-generated hologram formed thereon as a conjugate of the first diffractive structure, so that light travelling on a second optical path which may be incident on the second surface passes through the second and first diffractive stru

Abstract: All components and parts of a head-up displaying device are formed in a unit and secured to a dashboard or a rear panel of a vehicle. The displaying device has a case composed of a base member, a bottom plate and a cover. The base member is secured to the dashboard or the rear panel and forms a turntable with the bottom plate. An image projection unit, a control unit and a reflecting member are housed in the case, and a foldable flat combiner is pivotally secured to the cover of the case. A shade member is formed on the cover to prevent the image projection unit from coming into the driver's line of sight. The combiner is held by a holder which forms a hinge using clips secured to the case and shafts formed on the sides of the holder so that the inclination angle of the combiner may be adjusted.

Abstract: Heads-Up and heads-down displays employing holographic stereograms are provided. The stereograms can be oriented perpendicular to the user's line of sight (the 90.degree. case) or at angle to the line of sight (the "non-90.degree. case"). The stereograms are produced using a three-step process in which a series of two-dimensional perspective views are prepared, a H.sub.1 hologram is prepared from the two-dimensional perspective views, and a H.sub.2 hologram is prepared from the H.sub.1 hologram. For the non-90.degree. case, the two-dimensional perspective views are oriented at an angle relative to the plane of the H.sub.1 hologram during the preparation of that hologram. Similarly, during the preparation of the H.sub.2 hologram for this case, the H.sub.2 hologram is oriented at an angle relative to the H.sub.1 hologram. In this way, the viewing slits generated by the holographic stereogram are located in the vicinity of the user's eyes for the non-90.degree. case as is desired.

Abstract: A vehicle data display device which draws the attention of the driver to a particular sector of the road scene, including an optical system that presents to the driver a reduced virtual image of the road scene embellished with a luminous signal. The luminous signal can be used to designate a target for the driver and can be under the control of an onboard driving assistance system. The vehicle data display device can be integrated into the steering column or dashboard of the vehicle and facilitates perception of driving assistance or navigational data without the driver having to turn his attention away from the road.

Abstract: The device allows to compensate for the aberrations of the collimating and combining holographic optics by using a simplified scheme for the relay optics. Said relay optics comprises six lenses and a window; it is terminated at each end by a plane side and is disposed in a case. Said relay optics and the holographic optical element are determined taking into account average data for the thickness and curvature of the windshield. The accurate compensation for the windshield deviations is made at a closing glass plate whose thickness is varied. The Folding optical element is a simple reflecting plane mirror and has no correcting effect, which permits the translation along the optical axis of said relay optics and the cathode-ray tube generating the luminous image to be collimated.

Abstract: A head-up display for an automobile utilizing a light transmission hologram optical device as well as a light reflection hologram optical device. The head-up display is installed in a large truck or in a special freight car, such as a container car or a ready mixed concrete car, so that the head-up display informs a driver of information of conditions of dead ground of the car. The head-up display includes a hologram optical projection system and a holographic combiner. The projection system for projecting the light has a light source, an LCD for partially transmitting and shielding the light of the light source, and a light transmission hologram optical device for projecting the light. The holographic combiner for displaying the image includes a light reflection hologram optical device.

Abstract: The invention relates to a variable transparency electro-optical device comprising: at least one lens formed by an electro-optical cell (4) comprising a first plate (6) and a second plate (8) each provided with a control electrode (14, 16) and a sealing frame (10) interposed between the two plates to form a sealed volume enclosing an electro-optical material (12), voltage generating means (18) connected to said electrodes to apply a variable voltage to said material in order to automatically or manually vary the transmission of the cell (4) as a function of the ambient light. According to the invention the cell (4) comprises at least one element (6) charged with a photochromic substance having an absorption that varies in reversible manner as a function of the intensity of the light impinging on said cell. The invention has particular applications in devices for protecting the eyes.

Abstract: A vehicle turn signal and/or hazard light display is created by utilizing a pair of lamps mounted upon in or on the dash top cowl of a vehicle. The bulbs of each lamp include a filament having a V-shaped portion which, upon electrical energization of the filament, becomes incandescent and a like V-shaped light display is projected from the lamps toward and impinges upon the vehicle windshield and is thereat visible to the driver. The V-shaped portions of the lamp filaments are oriented to point "left" and "right," and thus when appropriately connected to the turn signal circuit, will display "left" and "right" signals upon the windshield, or both "left" and "right" signals simultaneously which is the universal "hazard" signal. Since vehicle windshields are multi-ply, the leftward and rightward pointing "V-shaped" displays are visible in pairs.

Abstract: A hologram includes an optically transparent base plate having first and second opposite surfaces. A hologram element is provided on the first surface of the base plate, and has a predetermined holographic pattern. An optically transparent member has first and second opposite surfaces. The first surface of the member faces the hologram element. An arrangement serves to prevent light, which successively passes through the transparent base plate, the hologram element, and the member and is then reflected at a boundary between the second surface of the member and an atmosphere, from travelling back to the hologram element.

Abstract: This invention relates to a display apparatus for a vehicle having a head up display with a hologram for reflecting display light from a displayer. The display apparatus for a vehicle according to the present invention comprises: a displayer for displaying vehicle information; a hologram having a reflecting function installed in the vicinity of a lower portion of a windshield, the hologram diffracting a display light from the displayer toward a driver of the vehicle; and a dark member attached to a rear face of the hologram to shield external light entering the hologram.

Abstract: An image display apparatus includes a plurality of image display elements respectively assigned to different partial image information regions of an image to be displayed, and a hologram optical element for diffracting a plurality of light beams from the plurality of image display elements and displaying the diffracted light beams as continuous single image information. By including a plurality of image display elements, each of the image display elements having a large number of pixels, and a hologram optical element for forming a synthesized image by diffracting a plurality of image light beams from the image display elements, the hologram optical element diffracts the plurality of image light beams so as to display a synthesized image by interpolating information between pixels of a plurality of images to be synthesized.

Abstract: A vehicular extreme position display system displays a stereoscopic image of a three-dimensional object near a vehicular extreme position. The system provides different levels in brightness on the displayed stereoscopic image to enhance the stereoscopic effect. The displayed stereoscopic image may be arranged to change in color and brightness depending on monitored background illuminance. Further, the display of the stereoscopic image may be arranged to automatically terminate when a preset condition is matched.

Abstract: An automotive signal lamp is provided including a lens illuminated by a first light source on a first side, a transmissive hologram adjacent the lens for providing an image when the first light source is activated, and a reflective hologram adjacent the transmissive hologram for providing an image when the first light source is nonactuated and the lens is illuminated by a second light source on a second side of the lens generally opposite the first light source.

Abstract: Head-up displays on motor vehicles often have double images and interfering reflections on the windshield. To avoid these, arrangements of linear polarization filters or shutter foils are suggested, which have particularly high light transmission. Arrangements of filter plates on a combiner inside of the windshield are also advantageous.

Abstract: A display device for motor vehicles in which an image on the display is reflected by a reflecting member on the windshield to allow the virtual image to be viewed by the driver. The display device includes a display having an upwardly facing display surface, a first prism having a vertical angle .theta. formed by two surfaces of a first prism arranged so as to face the driver with one of the two surfaces arranged so as to face the display surface of the display and a second prism having substantially the same vertical angle as the first prism and being arranged in mating relation to the first prism with the vertical angles thereof opposing each other. In one embodiment, the bottom surface of the second prism confronting the vertical angle .theta. is matted, whereas other surfaces than the two surfaces forming the vertical angle .theta. are coated in a dark color.

Abstract: Head-up displays on motor vehicles often have double images and interfering reflections on the windshield. To avoid these, arrangements of linear polarization filters or shutter foils are suggested, which have particularly high light transmission. Arrangements of filter plates on a combiner inside of the windshield are also advantageous.

Abstract: A head mounted display having an image source, an optical relay system and a combiner for producing an image from the image source to the eye of a pilot in which the optical system includes at least one diffractive surface to compensate for aberrations and distortions in the display.

Abstract: A hologram structure including a hologram layer including a half-tone pattern of transparent areas and reflection hologram areas, and a non-hologram half-tone pattern of areas that are substantially opaque to the range of wavelengths that comprises the spectral bandwidth of the holograms areas located adjacent the hologram layer, wherein the hologram areas are superimposed with selected areas of the non-hologram half-tone pattern.