JPH0879799A - Stereoscopic display system, and its synchronizing signal transmitter and synchronizing signal receiver - Google Patents

Abstract

PURPOSE: To reduce disturbance in an image seen through a shutter eyeglass to the utmost by noise immunity performance as to space transmission of a switching synchronizing signal so as to widen a service area even when malfunction due to signal transmission takes place. CONSTITUTION: A switching synchronizing signal from the equipment body 1 is given to an FM modulator 2, in which the signal is frequency-modulated and its FM signal is outputted from the FM modulator 2 and given to an electro/optic converter 3 and intensity modulation is applied to an infrared ray according to the FM signal. The infrared ray signal is emitted in the air. An optical/ electric converter 4 provided in addition to a shutter eyeglass 7 receives the infrared ray signal emitted in the air and converts the signal into an electric signal. An FM demodulator 5 demodulates the received signal to reproduce a switching synchronizing signal. A shutter drive circuit 6 is operated according to the reproduced switching synchronizing signal to alternately apply on/off drive to a left/right shutter of the shutter eyeglass 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION This invention is for two eyes, one for the right eye and one for the left eye.
Stereoscopic display system for displaying stereoscopic images by alternately switching high-dimensional images at high speed and driving shutter glasses worn by an observer alternately on and off in synchronization with switching between left and right images, and this system The present invention relates to a synchronization signal transmitting device and a synchronization signal receiving device that compose the.

[0002]

2. Description of the Related Art The following system is well known as one type of stereoscopic display system. That is,
A transmission device having a display control means for alternately switching and displaying two-dimensional images for the right eye and the left eye at high speed, and spatially transmitting a switching synchronization signal for the left and right images output from the display control means, and the transmission device. A receiver having shutter drive means for receiving the switching synchronization signal transmitted in space and for alternately driving on / off in accordance with the switching synchronization signal received by a right eye shutter and a left eye shutter of shutter glasses worn by an observer; It is a system equipped with.

The reason why the switching synchronization signal is spatially transmitted to the shutter glasses side in this way is to make the shutter glasses worn by the observer cordless and to enhance the practicality. In the conventional stereoscopic display system of this type, infrared rays are used as a medium for spatial transmission of the switching sync signal, and an infrared pulse signal as shown in FIG. 5 is adopted as a transmission format of the switching sync signal. Was there. In this conventional example, the start timing of the left eye period is designated by a narrow pulse signal, and the start timing of the right eye section is designated by a wide pulse signal.

[0004]

However, the conventional method for directly spatially transmitting the switching timing of the left and right images by infrared pulse signals having different widths has a problem that it is extremely vulnerable to ambient noise and the service area is narrow. . That is, if some noise source that generates an infrared pulse exists in the vicinity, the noise is erroneously recognized as a switching synchronization signal, and the shutter glasses are often inverted and driven at an incorrect timing. Further, if the distance between the infrared transmitter on the main body of the display device and the infrared receiver on the side of each of the shutter glasses becomes long, transmission errors (missing of received signal) increase, and the shutter glasses cannot be driven in reverse at the correct timing. The influence of the malfunction caused by the noise and the lack of the received signal extends to one field of the image for the right eye or the image for the left eye, and therefore the quality of the stereoscopic image viewed through the shutter glasses is severely deteriorated, resulting in a very ugly image. There was a problem.

The present invention has been made in view of the above-mentioned conventional problems. With respect to the spatial transmission of the switching synchronization signal, the noise resistance is enhanced, the service area is widened, and a malfunction due to the signal transmission occurs. However, it is still another object of the present invention to provide a stereoscopic display system or the like in which the disturbance of an image viewed through the shutter glasses is minimized.

[0006]

Therefore, according to the present invention,
Display control means for alternately switching and displaying two-dimensional images for the right eye and the left eye at a high speed, and outputting a switching synchronization signal synchronized with the switching display, and an FM modulator for FM-modulating the switching synchronization signal of the display control means. And a FM signal demodulator for FM demodulating the received switching sync signal, and a right eye shutter and a left eye of the shutter glasses according to the FM demodulated switching sync signal. A stereoscopic display system including a synchronization signal receiving device having a shutter drive circuit that alternately turns on and off a shutter. Infrared rays or ultrasonic waves are used as a medium for space transmission.

[0007]

The switching sync signal has a low frequency of about several tens to hundreds of hertz, and a carrier wave having a sufficiently high frequency is FM-modulated by this switching sync signal and spatially transmitted in the form of an infrared signal or an ultrasonic signal. Then, the noise resistance performance of this transmission line is improved, and thus the service area is expanded. Further, even if a transmission error occurs, it is rare that the image is lost over the entire field of the display image, and in most cases, only a part of the field is lost.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic circuit block diagram of a stereoscopic display system according to the first embodiment of the present invention.
In FIG. 1, the stereoscopic display system includes a synchronization signal transmitting device A attached to the device body 1 and a synchronization signal receiving device B attached to the shutter glasses 7.

The apparatus main body 1 on the side of the synchronizing signal transmitting apparatus A is provided with display control means for switching the two-dimensional images for the right eye and the left eye at high speed alternately on a two-dimensional display means such as a television monitor. The means outputs a switching synchronization signal synchronized with the switching display. FIG. 2 shows an example of the format of this switching synchronization signal. Here, the rectangular wave having a duty ratio of 50% represented by the right eye period and the left eye period “1” and “0” is used, but the format of the switching synchronization signal is not limited to this example, and it depends on the voltage value. Various methods such as a signal format in which the left and right periods are expressed and the left and right periods are expressed by the difference in frequency can be adopted.

Returning to FIG. 1 again, the switching synchronization signal from the apparatus main body 1 is input to the FM modulator 2, and a predetermined carrier wave is FM-modulated by the switching synchronization signal. The FM signal is output from the FM modulator 2 and input to the electrical / optical converter 3. The electric / optical converter 3 includes an infrared light emitting diode or an infrared laser diode and the like, and a drive circuit therefor.
Intensity modulation is applied to the infrared light output according to the FM signal from the FM modulator 2. The infrared signal thus intensity-modulated is radiated into space in a predetermined direction.

On the other hand, the synchronizing signal receiving device B receives the infrared signal spatially radiated from the electric / optical converter 3 described above,
It has an optical / electrical converter 4 for converting into an electric signal,
The electric converter 4 includes a light receiving element such as an infrared phototransistor and a light receiving signal amplifier. The output of the optical / electrical converter 4 is input to the FM demodulator 5, and the FM demodulator 4 demodulates the received signal and reproduces the switching synchronization signal.

The reproduced switching sync signal is supplied to the shutter drive circuit 6, and the shutter drive circuit 6 alternately turns on / off the right eye shutter and the left eye shutter of the shutter glasses 7 in accordance with the switching sync signal. That is, the right eye shutter and the left eye shutter of the shutter glasses 7 are alternately turned on / off in synchronization with the switching display of the images for the right eye and the left eye on the apparatus body 1, whereby a stereoscopic image can be seen.

FIG. 3 shows a schematic circuit block diagram of the second embodiment of the present invention. In FIG. 3, this second
In the embodiment, an ultrasonic wave generator 8 and an ultrasonic wave detector 9 are used instead of the electric / optical converter 3 and the optical / electrical converter 4 of the first embodiment.
It is configured using. Since other configurations are the same as those of the first embodiment, the same reference numerals are given to the drawings and the description thereof will be omitted. That is, in the first embodiment, infrared rays are used as the space transmission medium for the switching sync signal, but in the second embodiment, ultrasonic waves are used. Note that space transmission using visible light, ultraviolet light, or the like may be adopted.

FIG. 4 shows a schematic circuit block diagram of a third embodiment of the present invention. 4, in the third embodiment, a transmitting antenna 10 and a receiving antenna 1 are used instead of the electric / optical converter 3 and the optical / electrical converter 4 of the first embodiment.
1 is used. Since other configurations are substantially the same as those of the first embodiment, the same reference numerals are given to the drawings and the description thereof will be omitted. That is, in the third embodiment, radio waves are used as the space transmission medium for the switching sync signal.

[0015]

According to the present invention, a carrier wave having a sufficiently high frequency is FM-modulated by a low-frequency switching sync signal of about several tens to hundreds of hertz, and the FM signal is converted into an infrared signal or an ultrasonic signal for spatial transmission. To do. Therefore, the noise resistance performance of this transmission line is greatly improved as compared with the conventional method, and the service area is widened accordingly. Even if a transmission error occurs,
It is rare for an image to be lost over the entire field of a display image, and in most cases only a portion of one field will be lost.

[Brief description of drawings]

FIG. 1 is a schematic circuit block diagram of a stereoscopic display system (first embodiment).

FIG. 2 is a diagram showing an example of a format of a switching synchronization signal (first embodiment).

FIG. 3 is a schematic circuit block diagram of a stereoscopic display system (second embodiment).

FIG. 4 is a schematic circuit block diagram of a stereoscopic display system (third embodiment).

FIG. 5 is a diagram showing a format of a switching synchronization signal (conventional).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Device main body (display control means) 2 ... FM modulator 5 ... FM demodulator 6 ... Shutter drive circuit 7 ... Shutter glasses A ... Sync signal transmitter B ... Sync signal receiver

Claims (5)

[Claims] 1. A display control means for alternately and rapidly displaying a two-dimensional image for the right eye and a two-dimensional image for the left eye, and outputting a switching synchronization signal synchronized with the switching display, and a switching synchronization signal for the display control means is FM. A synchronization signal transmission device that spatially transmits the FM-modulated switching synchronization signal; an FM demodulator that performs FM demodulation of the received switching synchronization signal;
A stereoscopic display system comprising: a synchronization signal receiving device having a shutter drive circuit that alternately turns on and off a right-eye shutter and a left-eye shutter of shutter glasses in accordance with a M-demodulated switching synchronization signal. 2. A display control means for alternately and rapidly displaying a two-dimensional image for the right eye and a two-dimensional image for the left eye, and outputting a switching synchronization signal synchronized with the switching display, and a switching synchronization signal of the display control means for FM. A synchronization signal transmitting device, comprising: an FM modulator for modulating, and spatially transmitting the FM-modulated switching synchronization signal. 3. Receiving a spatially transmitted switching synchronization signal,
An FM demodulator for performing FM demodulation on the received switching synchronization signal, and a shutter drive circuit for alternately turning on / off the right-eye shutter and the left-eye shutter of the shutter glasses according to the FM-demodulated switching synchronization signal. Synchronous signal receiver. 4. The stereoscopic display system according to claim 1, wherein the medium for spatial transmission of the switching synchronization signal is infrared light, or the synchronization signal transmission device according to claim 2, or Item 5. The synchronization signal receiving device according to item 3. 5. The stereoscopic display system according to claim 1, wherein the medium for spatial transmission of the switching synchronization signal is an ultrasonic wave, or the synchronization signal transmission device according to claim 2, or The synchronization signal receiving device according to claim 3.