Binocular display devices typically include two display panels, such as liquid crystal display (LCD) panels, which are typically viewed through a pair of lens assemblies. Such structures also tend to be fairly heavy, uncomfortable to wear, and difficult to transport.
In order to obtain binocular viewing, the two display panels are aligned so that the images formed on the display panels appear to merge into a single stereoscopic image to the viewer. That alignment step is often limited to steps performed by the user, who is required to adjust the interpupillary distance (IPD) between the exit pupils of the lens assemblies so that they align with the individual's eye pupil spacing. That adjustment works best when the lenses and display panels are themselves properly aligned. Typically, the positions of each lens and display panel are dictated by features on a mounting frame. Further alignment between the lens and display panel may not be practical.
Embodiments of the present invention can provide a compact display that can be worn by a user in a similar manner to wearing eyeglasses, or if the user is wearing eyeglasses, the display can be supported at least in part by the eyeglasses. The display can include a nose bridge for resting on a user's nose, and earpiece stems for resting on the user's ears. If the user is wearing eyeglasses, the earpiece stems of the display can have support clip members which can engage and rest on the earpiece stems of eyeglasses for supporting the display. The display can also include a center support clip member which can engage and rest on the top of the frame of the eyeglasses for further supporting the display. The nose bridge can be retracted when the display is worn by a user wearing eyeglasses to accommodate the eyeglasses, or can be deployed when the display is worn by a user not wearing eyeglasses.
Embodiments of the present invention can also provide a compact head mounted display that can be folded in a compact manner for transport or storage. The display can include a housing having at least one LCD panel for viewing, and earpiece stems for resting on the user's ears. The earpiece stems can fold relative to the housing. In addition, each earpiece stem can include at least one intermediate folding joint so that the earpiece stem can be folded to be more compact than conventional earpieces. Each earpiece stem can also include at least one bend to allow folding in close relationship to the housing.
A particular embodiment of a binocular display device can comprise a frame, a first and second display panel, a first and second lens assembly, and a first and second alignment fixture. The first display panel can be mounted to the frame for forming a first image having a first display axis and the second display panel can be mounted to the frame for forming a second image having a second display axis. The first lens assembly can be mounted to the frame and have a first viewing axis and the second lens assembly can be mounted to the frame and have a second viewing axis. The first alignment fixture can be used for aligning the first display axis relative to the first viewing axis and the second alignment fixture can be used for aligning the second display axis relative to the second viewing axis. A fastener can then be used for fixing the first and second alignment fixtures in the respective alignment so that the first and second images are registered when binocularly viewed by a viewer through the first and second lens assemblies.
More particularly, the display panels can be liquid crystal display panels. At least one backlight can be used to illuminate the display panels. The display device can further comprise an interface circuit coupled to the display panels to provide power and a data signal.
Furthermore, the alignment fixtures can allow for vertical and horizontal adjustment of the display panels relative to the frame.
A particular application of the binocular display device is as a head-mountable display. To that end, the display device can further comprise a first earpiece and a second earpiece for mounting the frame to a viewer's head. The earpieces can include a respective hinge disposed along the longitudinal length of each earpiece. In addition, eyeglass mounts can be used to facilitate mounting of the frame to eyeglasses. Those eyeglass mounts can include a retractable nose bridge.
When the components of a binocular display are first assembled, the two display panels are sometimes not aligned in acceptable positions, resulting in poor viewing. Adjusting the display panels by eye can be slow and provide inconsistent results.
An alignment system can be used to more quickly, easily and consistently aligning first and second display panels of a binocular display device into more optimum positions than achieved by previous methods. Such a binocular display device typically has a first lens assembly for viewing the first display panel and a second lens assembly for viewing the second display panel.
The alignment system can include a camera system for viewing or observing the first display panel of the binocular display device through the first lens assembly, and for viewing or observing the second display panel through the second lens assembly. Display panel alignment indicia can be located on the first and second display panels. A viewing screen system can be included for viewing images of the display panel alignment indicia on the first and second display panels which are provided by the camera system. The viewing screen system can include baseline indicia whereby the first and second display panels can be adjusted into an alignment position for binocular viewing by adjusting positions of the display panels until the images of the display panel indicia shown on the viewing screen system are located relative to the baseline indicia in a manner that indicates acceptable alignment.
In particular embodiments, a display panel indicia source can be employed for providing the first and second display panels with the display panel alignment indicia. A viewing screen indicia source system can be employed for providing the viewing screen system with the baseline indicia. The display panel alignment indicia and the baseline indicia can each comprise a crosshair that can be aligned with each other.
The alignment system can include a mounting fixture for securing the binocular display device in a fixed position. The camera system can include a first camera for viewing the first display panel and a second camera for viewing the second display panel. The first and second cameras can be mounted relative to the mounting fixture. The first and second lens assemblies of the binocular display device can each have an optical axis which are spaced apart from each other by a distance D1. The first and second cameras can be spaced apart from each other about the same distance D1 for alignment with respective first and second lens assemblies. The first and second cameras can be positioned on opposite sides of a longitudinal axis. The first and second cameras can be prefocused on a location on the longitudinal axis at a distance D2 which allows the cameras to focus on the first and second display panels when viewed through the first and second lens assemblies of the binocular display device. The viewing screen system can include first and second viewing screens. The first viewing screen is capable of viewing images seen by the first camera and the second viewing screen is capable of viewing images seen by the second camera.
The present system also includes a method of aligning first and second display panels of a binocular display device. Such a binocular display device typically has a first lens assembly for viewing the first display panel and a second lens assembly for viewing the second display panel. A camera system can view or observe the first display panel of the binocular display device through the first lens assembly, and can view or observe the second display panel through the second lens assembly. Display panel alignment indicia can be provided on the first and second display panels. A viewing screen system can view images of the display panel alignment indicia on the first and second display panels which are provided by the camera system. The viewing screen system can include baseline indicia. The first and second display panels can be adjusted into an alignment position for binocular viewing by adjusting the positions of the display panels until the images of the display panel indicia shown on the viewing screen system are located relative to the baseline indicia in a manner that indicates acceptable alignment.
In particular embodiments, the first and second display panels can be provided with the display panel alignment indicia from a display panel indicia source. The viewing screen system can be provided with the baseline indicia from a viewing screen indicia source system. Each display panel alignment indicia and baseline indicia can be displayed as a crosshair that can be aligned with each other.
The binocular display device can be secured in a fixed position with a mounting fixture. The first display panel can be viewed with a first camera of the camera system and the second display panel can be viewed with a second camera of the camera system. The first and second cameras can be mounted relative to the mounting fixture. The first and second lens assemblies of the binocular display device can each have an optical axis which are spaced apart from each other by distance D1. The first and second cameras can be spaced apart from each other the about same distance D1 for alignment with respect to first and second lens assemblies. The first and second cameras can be positioned on opposite sides of the longitudinal axis. The first and second cameras can be prefocused on a location on the longitudinal axis at a distance D2 in order to allow the cameras to focus on the first and second display panels when viewed through the first and second lens assemblies of the binocular display device. Images seen by the first camera can be viewed with a first viewing screen of the viewing screen system, and images seen by the second camera can be viewed with a second viewing screen of the viewing screen system. At least one of the vertical and horizontal positions of the first and second display panels can be adjusted during the alignment process.
During calibration of the alignment system, the camera system can be prefocused on a reference target that is at a location on the longitudinal axis at a distance D2. The baseline indicia can be calibrated to be located at the proper position on the viewing screen system for the alignment process by projecting images of the reference target viewed by the camera system on the viewing screen system. The position of the baseline indicia can be adjusted on the viewing screen system until the baseline indicia is located relative to the images of the reference target in a manner that indicates acceptable alignment. In some embodiments, the baseline indicia can be superimposed over at least portions of the reference target.
The foregoing and other objects, features and advantages of the invention will be apparent from the following description of particular embodiments, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
Commercial embodiments of the binocular display device are available from Kopin Corporation of Taunton, Mass. under part numbers BDM-230K and BDM-922K. Both models are lightweight at 26 grams and 28 grams, respectively. Both models also offer low power consumption at less than 450 mW and 960 mW, respectively. The BDM-230K measures 97.5 mm×22.0 mm×23.75 mm, provides QVGA resolution (320×240) at 230K colors, and offers a 24-degree field of view. The BDM-922K measures 95.6 mm×22.3 mm×31.15 mm, provides VGA resolution (640×480) at 922K colors, and offers a 32-degree field of view. Both models operate on a 3.3 volt power supply and auto-selects NTSC or PAL standard video sources.
The electrical components are mounted to the rear side of the main housing 12, with rear mounting screws, as shown. Displayed images are formed on a first (or right) display panel 14A, and a second (or left) display panel 14B. The right 14A and left 14B display panels can be liquid crystal display (LCD) panel assemblies and can include LED or other suitable backlighting. Each display panel has an associated optical axis 115A, 1115B. Particularly suitable display panels are CyberDisplay® family microdisplays, which are commercially available from Kopin Corporation of Taunton, Mass. under part numbers KCD-QDNF-AA/BA and KCD-VDCF-AA/BA, although other suitable microdisplays having diagonal dimensions of less than about 25 mm may also be used.
The circuit board 30 is secured to center rear of the main housing 12, although other mounting locations may be used. The circuit board is designed to receive video signal and power inputs from external sources through data and power input ports 35. The right 14A and left 14B display panels can be electrically connected to the circuit board 30 and can be provided with moving picture images such as video images, computerized images, still images, etc. The video/image data signals are provided from the circuit board via a ribbon cable 32A, 32B to each display panel 14A, 14B. The circuit board 30 also provides power to the display panels via a power connection 34A, 34B.
The binocular display device 10 can also include a vertical adjustment frames 9A, 9B and a horizontal adjustment frames 11A, 11B for adjusting the vertical and horizontal positions of each display panel 14A and 14B. The adjustment frames are thus fixtures used to align the various optical axes relative to the center axis 100 of the main housing 12. It should be understood that in certain embodiments, the display panels may have to be adjusted parallel to the axes.
In one possible binocular display device 10, the distance D1 can be set at a 63.5 mm interpupillary distance (IPD) standard, the distance D2 can be two meters, ½ diopter and 0.916 degrees (55′), and the distance D3 can be four meters, ¼ diopter and 0.458 degrees (27.5′). The particular specifications of the optics are as follows:
The surface data detail is as follows:
The listing of surface 7 sag is as follows (units are millimeters):
Best Fit Sphere residual: 2.467121E-−001. (rms)
The listing of surface 9 sag is as follows (units are millimeters):
Best Fit Sphere residual: 1.907468E−001. (rms)
The listing of surface 11 sag is as follows (units are millimeters):
Best Fit Sphere residual: 1.618948E−001. (rms)
The listing of surface 13 sag is as follows (units are millimeters):
Best Fit Sphere residual: 2.041468E−012. (rms)
To obtain the desired acceptable optical convergence of display panels 14A and 14B at distance D2 on center axis 100, the positions of displays 14A and 14B should be properly positioned or aligned relative to the lens assemblies 20A and 20B and center axis 100. When a binocular display device 10 is initially assembled, the display panels 14A and 14B are typically not in acceptable positions. Adjusting the positions of the display panels 14A and 14B by eye can be slow and difficult, with inconsistent results.
A particular alignment system is therefore desired that can be used to more quickly, easily, and consistently optically aligning the displays 14A and 14B of a binocular display device 10 as well as other binocular display devices, in acceptable locations for suitable binocular viewing. Discussion of the alignment of one possible binocular display device 10 now follows.
Once the binocular display device 10 is secured to the mounting fixture 224, a display panel indicia source 242 can be electrically connected to the binocular display device 10, such as at the circuit board 30, for providing the right 14A and left 14B display panels with display alignment indicia 251. In one embodiment, the display alignment indicia 251 can be a crosshair having vertical 247 and horizontal lines 249, which is centered along the central optical axis 115 of the display panels 14A and 14B, for example, as seen on the right display panel 14A shown in
Referring back to
An example of what is shown on the viewing screens 234A and 234B can be seen in
Referring to
The process for aligning display panel 14B is similar, where the display panel alignment indicia 251 for display panel 14B can be moved in alignment with the baseline indicia 252 on viewing screen 234B with movement or adjustment of the display panel 14B on the binocular display device 10. The display panels 14A and 14B can be adjusted in a symmetrical manner.
Typically, the display panels 14A and 14B are moved until the crosshair of the display alignment indicia 251 on the screen 244 is aligned or superimposed over the baseline indicia 252 so that the central optical axis 115 of the display panels 14A and 14B is positioned at the center 250 of the baseline indicia 252. Such adjusting of the display panels 14A and 14B can be performed manually or can be automated, for example, by suitable machinery, robots, etc. If the indicia 251 and 252 cannot be superimposed over each other, it can be acceptable for the indicia 251 and 252 to be positioned close to each other in a symmetrical manner and within a tolerance range. It is possible that, on occasion, a display panel 14A or 14B might not require any adjusting, or might only require adjustment in one direction. Once adjusted, the display panels 14A and 14B can be locked in place with adhesives or by other suitable means.
Referring to
Referring to
The cameras 226A and 226B can be prefocused or precalibrated on a reference target 256 (
The position or location of the baseline indicia 252 on each screen 234A and 234B can be precalibrated to be at a suitable position for the alignment process. This can be accomplished by projecting the images of the crosshairs 258A and 258B of the reference target 256 as viewed by the cameras 226A and 226B onto the viewing screens 234A and 234B. The baseline indicia 252 can then be projected on each viewing screen 234A and 234B. The positions of the baseline indicia 252 on each viewing screen can be adjusted by adjusting controls on the viewing screen indicia sources 230A and 230B until the baseline indicia 252 are superimposed over the images of the crosshairs 258A and 258B on each viewing screen 230A and 230B. The baseline indicia 252 are then in calibrated positions on each viewing screen 230A and 230B.
An alternative method of precalibration can be accomplished by securing a binocular display device 10 to the mounting fixture 224 that already has the display panels 14A and 14B in suitable alignment. The display panel indicia source 242 can then be connected in communication with the binocular display device 10 and display panel alignment indicia 251 is projected onto the display panels 14A and 14B in a centered manner. The baseline indicia 252 can be projected on each viewing screen 234A and 234B and the position of the baseline indicia 252 can be moved by adjusting the controls on the viewing screen indicia sources 230A and 230B until the baseline indicia 252 are superimposed over the display panel alignment indicia 251 on each viewing screen 230A and 230B.
In one embodiment, the display panel indicia source 242 can be a video source which can be connected in communication with the binocular display device 10 by a cable 240, a video converter 238, and a cable 236. The cable 240 can be a video cable, the video converter 238 can convert VGA to NTSC, and cable 236 can be a BDM cable. The cameras 226A and 226B of the camera system 226 can be CCD cameras, and can have a 12V DC/500 mA regulated power supply and a 12.0 mm FL micro video lens. The cameras 226A and 226B can be connected in communication with the viewing screen indicia sources 230A and 230B by connectors 228A and 228B, for example, BNC male to NTSC male connectors. The viewing screen indicia sources 230A and 230B can be TG100 single camera adjustable video target generators with a thumbwheel position control. The viewing screens 234A and 234B can be connected in communication with respective viewing screen indicia sources 230A and 230B with cables respective 232A and 232B, such as BNC male to BNC male cables. The viewing screens 234A and 234B can be 12 inch monochrome monitors with EIA/CCIR auto-sensing.
Although a particular display panel indicia source 242 and viewing screen indicia source system 230 have been described, it is understood that other suitable devices for producing indicia can be employed. Although the display panel alignment indicia 251 and the baseline indicia 252 are shown in one embodiment to be crosshairs that are superimposed during the alignment process, it is understood that the indicia 251 and 252 can be of many different configurations. For example, the indicia 251 and 252 can be other geometric indicia, for example, circles, squares, polygons, etc., or can be complex images, patterns, configurations, icons, etc., which are aligned. In addition, the indicia 251 and 252 do not have to be identical or superimposed, for example, one can represent a target, puzzle, half an image, etc., and the other can represent the dart, missing piece of the puzzle, the other half of the image, etc., which are positioned in the appropriate location for alignment purposes. Also, one or both of the display alignment indicia 251 and 252 do not have to be electronically generated on the display panels 14A and 14B, or the viewing screens 234A and 234B. For example, one or both of the indicia 251 and 252 can be physically added to the display panels 14A and 14B or viewing screens 234A and 234B, or can be physical characteristics, such as an edge, outline, particular feature, etc. With differing indicia 251 and the configuration of the reference target 256 can vary.
Although the display panels 14A and 14B are shown to have a single unitary screen, the display panels 14A and 14B can include multiple screens joined together to form a composite display panel. Additionally, in some embodiments, the mounting fixture 224 can be on a mechanism such as a robotic arm, or a robotic gripper can serve as the mounting fixture 224 for positioning the lens assemblies 20A and 20B of the binocular display device 10 in alignment with the camera system 226.
Although in one embodiment the cameras 226A and 226B are mounted to the mounting fixture 224, alternatively, the cameras 226A and 226B can be mounted relative to the mounting fixture 224 without being mounted directly to the mounting fixture 224. Although
Although embodiments of the disclosed alignment system have been shown and described to align the display panels 14A and 14B of the binocular display device 10 depicted in
Returning to
In some embodiments, only a single LCD display 14 may be positioned within the HMD housing 310. The displayed image on a single LCD display 14 can be binocularly viewed by the wearer, or a single display device can be worn as a monocular display. A user 300 can also wear the HMD 310 while also wearing eyeglasses 350.
The HMD 310 can also have a front center support clip member 330 for resting on and engaging the top central region of the frame of the eyeglasses 350 for further supporting the HMD 310 on the eyeglasses 350. If desired, the clip 330 can extend most or all of the length of the frame of the eyeglasses 350, or multiple clips 330 can be employed. Clips 320 can also be configured in a similar manner. Clips 320 and/or clip 330 can provide resilient gripping, and can provide proper alignment of the display 310 laterally or along the viewing axis.
The display 310 can also have a nose bridge piece or support member. The nose bridge can be retracted when the user is wearing eyeglasses to accommodate the eyeglasses, or deployed if the user is not wearing eyeglasses.
Referring to
In another embodiment, as shown in
It should also be understood that the earpiece stems of the HMD's do not have to fold and can be formed integrally with the housing. In some embodiments of the displays that may be worn with eyeglasses, the earpiece stems can be truncated or omitted. In such embodiments, the displays can include additional clip members, clamps, set screws, etc. in other locations for engaging the eyeglasses for stability. In some embodiments, the eyeglasses can be secured within the housing of the displays. Clips or securing members can also be positioned on the bottom of the eyeglasses to aid in securement. The eyeglasses can also include attachment devices, arrangements or features incorporated into the frames, for example holes, threaded holes, pins, locking tabs or receptacles, etc., to which mating fastening devices, arrangements or features on the displays can engage for locking the displays to the eyeglasses. The BDM 10 can also be fabricated so as to be directly coupled to earpieces.
The housing 520 can have contours 521 on the front surface, which provide an appearance similar to eyeglass lenses. A ridge 526 can extend on the front surface. A nose bridge 528 can be included for resting on the user's 524 nose. A connecting rib, piece or member 522 can extend across the front of the housing 520 and connect to the earpiece stems 516. The connecting member 522 can be secured to the housing 520 or can be integrally formed or molded into the housing 520.
The earpiece stems 516 can include more than one folding joint, for example, first and second folding joints 518a and 518b, as shown, and more than one stem segment, for example, first and second stem segments 516a and 516b, as shown. The first folding joints 518a can pivotably or foldably connect the earpiece stems 516 to the connecting member 522. The second folding joints 518b can be positioned at an intermediate location on each earpiece stem 516 and can pivotably or foldably connect stem segments 516a and 516b to each other. The first folding joint 518a can allow the first segment 516a of each earpiece stem 516 to fold behind the rear of the housing 520. The second folding joint 518b can allow the second segment 516b to be folded relative to the first segment 516a, thereby reducing the length or size of the earpiece stem 516. The joints 518a and 518b can fold or rotate within a predetermined and fixed arc or angle, and can have locking mechanisms.
The earpiece stems 516 can also include one or more bends, for example, bends 517a and 517b, as shown. The bends 517a and 517b can be shaped to allow the earpiece stems 516 to be folded around the rear of the housing 520 more closely as well as for comfort. The folding joints 518a and 518b can fold in an inwardly manner and, in combination with the bands 517a and 517b, can allow the segments 516a and 516b to be folded closely to the housing 520 in a compact manner for storage. In particular, the resulting assembly can fit in the palm of a user's hand when folded, and can be of a size comparable to a pair of eyeglasses. In some embodiments, each earpiece stem can have more than two joints and two segments.
While this invention has been particularly shown and described with references to particular embodiments, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the scope of the invention.
This application claims the benefit of U.S. Provisional Application Nos. 60/631,062, filed Nov. 24, 2004, 60/691,955, filed Jun. 17, 2005, 60/726,006, filed Oct. 11, 2005, and Provisional Application, filed Nov. 14, 2005, titled “Compact Head Mounted Display” (Attorney Docket No. 0717.2062-000). The entire teachings of the above applications are incorporated herein by reference.
Number | Date | Country | |
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60631062 | Nov 2004 | US | |
60691955 | Jun 2005 | US | |
60726006 | Oct 2005 | US | |
60736502 | Nov 2005 | US |