WO2000018140A1

WO2000018140A1 - Projection display system and device with high bandwith wireless communication for projection display data

Info

Publication number: WO2000018140A1
Application number: PCT/EP1999/006568
Authority: WO
Inventors: Adrianus J. S. M. De Vaan; Marc E. A. Corthout; Franciscus P. M. Budzelaar
Original assignee: Koninklijke Philips Electronics NV
Current assignee: Koninklijke Philips NV
Priority date: 1998-09-18
Filing date: 1999-09-06
Publication date: 2000-03-30
Anticipated expiration: 2001-03-18
Also published as: KR20010032185A; TW450009B; JP2002525695A; EP1046305A1

Abstract

A display system has projector means with image entering means that feed display panel means for generating one or more light beam channels for subsequent projection through optical imaging means. The system further has a screen subsystem for accommodating a projected image thereon, and also high-bandwidth light sensor means for immediate reception of projection display data from the image entering means. In particular, the light sensor means have been co-integrated with one or more solid-state display panels for receiving projection display data along one or more light beam channels within the projector means.

Description

Projection display system and device with high bandwith wireless communication for projection display data.

BACKGROUND OF THE INVENTION

The invention relates to a system as recited in the preamble of Claim 1. The abstract of EP Al 484 571 discloses an optical front projection system for television display, wherein the optical system also serves for transferring infrared signals which provide the TV signal information to the projector that contains an infrared detector array, the detector array being located slightly outside the projected image. The reference also proposes to transmit the RGB signal components through spatially distributed transmission channels.

The present inventors have recognized the gradually increasing resolution requirements for such projection systems, which would necessitate a continual increase of available transfer bandwidth. In turn, such feature is causing increased concern over the effects of electromagnetic interference inside the projector, which should conform to what has been abbreviated as Electro Magnetic Compatibility EMC. The problem to some extent may be lessened by raising the number of connections, but such parallelism is costly and space within the projector is dear. A further object should be to restrict the connections between the drive electronics and the display panel(s) as much as possible. SUMMARY TO THE INVENTION

In consequence, amongst other things, it is an object of the present invention to increase the bandwidth inside the projection mechanism towards the display panel(s), whilst at the same time avoiding undue electromagnetic interference, creating freedom for a designer to put receiver parts at unused spaces within the projector architecture, whilst still avoiding wiring problems. Now therefore, according to one of its aspects the invention is characterized according to the characterizing part of Claim 1.

The feature that the receiver array has been co-integrated with one or more display panels relieves a designer from much of the burden that is being posed by EMC requirements. In fact, various optical system axes can now essentially coincide, because the optical elements pertaining to opposite transfer directions of light energy can be joined structurally and permanently. A similar set-up would pertain to rear projection systems.

The invention also relates to a projection device for beam production in such system. Further advantageous aspects of the invention are recited in dependent Claims. BRIEF DESCRIPTION OF THE DRAWING

These and further aspects and advantages of the invention will be discussed more in detail hereinafter with reference to the disclosure of preferred embodiments, and in particular with reference to the appended Figures that show: Figure 1, an implementation of the invention;

Figure 2, the position of the receiver in the light-valve panel;

Figure 3, an inventive embodiment with three transmissive panels;

Figure 4, an inventive embodiment with three reflective panels;

Figure 5, an embodiment of a mechanical interconnect; Figure 6, a CCD array to detect variations on the screen.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Figure 1 shows a perspective image of an implementation of the invention, that for clarity has been represented with a single channel. The system may have black-and-white display. Alternatively, colour display can be effected through a multi-colour display panel. At left is the housing of the projector device with the projection lens and the imaging area. The light valve(s) of the latter can be constructed as an LCD-display, an LED panel, a Deformable Mirror Device that selectively changes the reflection direction, or otherwise, and functions as object. This object is imaged and enlarged at right on a 60" tripod-supported screen. As sources for the audio- video information a Video Cassette Recorder and a Personal Computer have been shown schematically. Below the image, a four-transmitter array operates as object in the same optical system, which is imaged immediately above the light valve area at left. In addition to the above, the projector can have one or more second data transmitter cells to transfer signals in the reverse direction from the transmitter-receiver arrays as shown. These second transmitter cells would combine with a corresponding receiver facility, such as immediately below the screen. In this way, non-display data may be transferred bidirectionally, such as in a control signal dialog organization.

Figure 2 shows a possible position of the receiver in the light valve panel. In the center, the light valve matrix area 20 has been clearly shown, part of its cells 22 being represented in a much enlarged manner for clarity. At the edges of the array, the Row Drivers 24 and the Column Drivers 26 for the light valve matrix area 20 have been shown. Item 34 indicates three source signal detectors that allow to receive the display signal, as well as, if the case be, various control signals for the panel as a whole.

Item 32 represents a solar cell area for powering the panel through receiving ambient or stray light so that the control parts of the panel may operate in isolation from mains or battery power. Item 28 indicates electronics for signal conditioning such as scaling, gamma correcting, or removing artifacts. Power regulation for the panel is through item 30. The whole of Figure 2 has been configured as a single integrated circuit panel. Distribution over two or more panels, each with their LCD and detector functionality, would be feasible as well. For simplicity, the on-chip interconnection patterns have been omitted from the Figure. The overall configuration is that of the preceding Figures. For brevity, the facility for non-display data transmission considered with respect to Figure 1 has been left out of consideration here.

In contradistinction with Figure 1, Figure 3 shows an inventive embodiment with three transmissive display panels. The projection device has been indicated by a drawn line and comprises light source 40 with paraboloid mirror and lens 42. Mirror 44 "folds" the white light beam for greater compactness. Dichroic mirrors 48, 50 separate the beam into three mono-colour beams R, G, B, that by further fold mirrors 52, 54, 56 are projected on respective transmissive display panels 58, 60, 62 each provided with a further lens. Through dichroic prism 64 the three beams are fused to white light colour beam 66 that has been symbolized as a large arrow. This leaves the projector through projection lens system 68 for subsequent projection on the display screen. Image data sources, such as a VCR or a Personal Computer are connected to an electronic board that feeds an internal transmitter array 70. This comprises three transmitter subsystems, one for each of the three colours, so that each of the three display panels receives its own image and/or control data without a need for electrical and interference-prone HF interconnect to its silicon arrangement. The transmitters may be laser- based or not. The connection from the image data sources outside the projection device may be optical as well, in a configuration as shown with respect to Figure 1. In such case, the projection may be from a diffuse light source through the overall optical focusing system. An alternative is a coherent and narrow-beam immediate light source such as a laser externally from the imaging lens system. Apart from the inserting mechanism for the data beams, the elements of Figure 3 are conventional. For brevity, data transfer in the opposite direction from the screen subsystem to the projection device has not been shown in the picture.

Figure 4 shows an inventive embodiment with three reflective panels. Light source 40, projection lens 68, transmitter array 70 and the image data sources correspond to Figure 3. The combination of beam splitter 72 and the so-called philips-prism first separate the white light beam into the three primary colours that impinge on respective mono-colour reflective display panels 74, 76, 78. The prism receives the light beams from the transmitter array for similar projection on the receivers that are co-integrated with the display panels, so that the data therein may be used for modulating the display panel reflection. Due to reflection on the display surface, the state of optical polarization changes in dependence of the type of picture information. This allows to use the diagonal plane shown either as a mirror when the light enters from below, and as a semireflective plane when the reflected light returns from the right side. Subsequently, the projection image data are fused by the prism and are reflected on projection lens system 68 as shown with respect to Figure 3. The connection of the image data sources may be configured as has been discussed with respect to Figure 3 already. Apart from the inserting mechanism for the data beams, the elements of Figure 4 are conventional.

Figure 5 shows an embodiment of a mechanical interconnect of a display panel or light valve for use in reflection. The integrated circuit proper has been indicated as a dark block, that has been co-integrated with a receiver array at right. Electric power connects to the circuit, and the mechanical interconnections through screws have been shown as well. Light- transmissive plate 86 makes for a leakage-tight sealing. As shown, the receiver array is located outside the leakage-tight protective sealing. A particularly advantageous configuration has the receiver array also located more centrally and within the protective sealing. In this manner, the silicon gets a more compact shape for area and cost reduction, as has already been suggested by the configuration in Figure 2. For simplicity, none of the further circuitry features of Figure 2 have been shown in Figure 5. They may generally be located within the protective sealing.

Figure 7 shows a CCD array to detect variations on the screen, placed at the position of the "image" in Figure 6. This allows to use the complete screen as one or more control buttons, such as for controlling exchanges of the image, changing of the light level, or other. An indicator may be put at the position of the CCD, to operate as a wand or similar mechanism. Generally, the above disclosure has been succinct in instances where various parts by themselves might be considered as part of the general art knowledge.

Claims

CLAIMS:

1. A display system having projector means provided with image entering means that feed display panel means for generating one or more light beam channels for subsequent projection through optical imaging means, said system further having a screen subsystem for accommodating a projected image thereon, and said system furthermore comprising high- bandwidth light sensor means for immediate reception of projection display data from said image entering means, characterized in that the light sensor means have been co-integrated with one or more solid-state display panels for receiving projection display data along said one or more light beam channels within said projector means.

2. A system as claimed in Claim 1, wherein said light sensor means are arranged for cooperating with light transmitter means also arranged within said projector means.

3. A system as claimed in Claim 1, wherein said light sensor means are furthermore arranged for receiving control signals for controlling said display panel means.

4. A system as claimed in Claim 1, wherein said screen subsystem has remote wireless transmitter means for feeding said sensor means external to said optical imaging means.

5. A system as claimed in Claim 1, wherein said screen subsystem has said remote wireless transmitter means disposed substantially in the screen plane.

6. A system as claimed in Claim 1, wherein said screen subsystem has image and/or control data transmitter means.

7. A system as claimed in Claim 1, wherein said display panel means are provided with powering solar cell means.

8. A system as claimed in Claim 1, wherein said display panel means are provided with signal conditioning circuitry.

9. A system as claimed in Claim 1, having said sensor means co-located with said one or more solid-state display panels inside a protective sealing.

10. A projection device for beam production in a system as claimed in Claim 1, provided with image entering means that feed display panel means for generating one or more light beam channels for subsequent projection through optical imaging means, and said device furthermore comprising high-bandwidth light sensor means for immediate reception of projection display data from said image entering means, characterized in that the light sensor means have been co-integrated with one or more solid-state display panels for receiving projection display data along said one or more light beam channels within said projector means.

11. A device as claimed in Claim 9, wherein said light sensor means are arranged for cooperating with light transmitter means also arranged within said projector means.

12. A device as claimed in Claim 9, wherein said light sensor means are furthermore arranged for receiving control signals for controlling said display panel means.

13. A device as claimed in Claim 9, wherein said display panel means are provided with powering solar cell means.

14. A device as claimed in Claim 9, wherein said display panel means are provided with signal conditioning circuitry.