JP3758280B2 - Head-mounted display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a head-mounted display device that visually recognizes an image formed by an image display element by enlarging a virtual image, and particularly relates to a circuit configuration and arrangement when used as a display of a personal computer, a portable terminal, or the like.
[0002]
[Prior art]
In recent years, various head-mounted display devices (HMDs) have been proposed in order to meet the demand for improving the portability of video and data displays. As a conventional head-mounted display device, for example, a head-mounted image display device described in JP-A-8-237575 is known. Details will be described below with reference to FIGS. 11 and 12.
[0003]
In FIG. 11, the image information to be displayed is sent from the video reproduction device (501) such as video to the electric circuit (504) of the holding means integrated HMD (503) mounted on the head of the user (502). . The electric circuit (504) performs all processing for displaying an image on the liquid crystal display element. The signal processed by the electric circuit (504) is transmitted to the display unit (508) by the connector (507) provided on the eaves (506) unit of the cap (506) which is the wiring (505) and holding means.
[0004]
FIG. 12 is a diagram for explaining a typical display unit (508), and does not completely match the components of the display unit (508). At least a liquid crystal panel (511), a light source (512), a lens (513), and a mirror (514) are provided, and image information displayed on the liquid crystal panel (511) is transmitted to the lens (513) via the mirror (514). The image is magnified and displayed as a virtual image (515) by the lens (513), and is projected on the user's eye (516).
[0005]
[Problems to be solved by the invention]
However, in the HMD described above, since all the image information sent from the signal source is processed in the electric circuit, it is impossible to reduce the size of the circuit unit in the apparatus main body. Furthermore, since the number of signals transmitted to the display unit is large, the wiring cable is not gathered, leading to a result of impairing the mounting feeling.
[0006]
In addition, since the signal output from the circuit section is directly applied to the liquid crystal panel, it is transmitted as a large amplitude signal, and there is no noise and low power drive circuit / display due to power and noise mixing during transmission. Is difficult to realize. In particular, when the signal source displays image data for a personal computer or a portable terminal, it is necessary to process many times the operating frequency of the NTSC video signal. The deterioration of the is remarkable.
[0007]
In addition, since the connection part between the cap-shaped holding means and the display part is constituted by a connector that transmits the image signal sent to the display part, there is a risk of disconnection, poor contact, etc. in the connector part. is there.
[0008]
In the embodiment in which the hat-shaped support means is exchanged according to the size of the user's head, the interface unit for inputting the image information sent from the signal source becomes important. There was no detailed explanation and it was unclear.
[0009]
The present invention is for solving the above-mentioned problems, and the object of the present invention is to realize low power while ensuring a clear display without noise first, and secondly with excellent weight balance, It is to provide an HMD that is rich in workability and safety.
[0010]
[Means for Solving the Problems]
The head-mounted display device according to claim 1 is an optical unit comprising an image display element and a magnifying optical system for enlarging an image formed by the image display element, and the optical unit is placed in front of the user's head. In a head-mounted display device comprising a holding means for fixing and an image processing circuit for performing processing for displaying an image signal on an image display element, the image processing circuit is connected to a low voltage system near the back of the holding means. A high voltage system circuit is separately arranged in the circuit and the optical unit, and the low voltage system circuit and the high voltage system circuit are electrically connected.
[0011]
According to the above configuration, in the circuit mounted on the apparatus main body, the number of outputs of the high voltage system circuit output to the liquid crystal panel with respect to the number of output signals of the low voltage system circuit is approximately double that of the low voltage system. The number of cables for transmitting signals from the low voltage system circuit to the high voltage system circuit can be reduced by separately arranging the high voltage system circuit at the back of the circuit and immediately before the liquid crystal panel. Accordingly, the transmission cable itself can be made very thin and space efficiency can be improved, so that a small and lightweight HMD can be realized. Furthermore, by arranging the circuits separately according to the voltage level, it is possible to prevent noise from being mixed between the circuits, so that a clear display without noise can be provided. In addition, the circuit scale placed on the face side can be reduced compared to the circuit scale near the back of the head, and there is no weight on the face of the user when the device is mounted, resulting in a good weight balance and misalignment. Therefore, the user can work without feeling tired.
[0012]
The head-mounted display device according to claim 2, wherein the low voltage system circuit has a drive voltage for processing the image signal input from the signal source and a synchronization signal for determining a horizontal / vertical display position of the screen. The high voltage system circuit is a circuit that is processed with a voltage other than the low voltage system circuit, that is, a drive voltage of 5 V or more.
[0013]
According to the above configuration, if the voltage level processed by the low voltage system circuit is 5 V or less, the LVDS (Low Voltage Differential Signaling) which has recently been proposed, as well as the voltage levels of TTL, CMOS, etc. which are conventionally known. ) Is also included, so it can be applied to any signal source. Furthermore, with regard to the high voltage system circuit, it is possible to set a high voltage output corresponding to an arbitrary liquid crystal panel, and an HMD having a low power loss and high versatility can be realized.
[0014]
4. The head-mounted display device according to claim 3, wherein the high voltage system circuit drives a liquid crystal panel and a buffer amplifier for amplifying the modulation signal obtained by extending the time of the image signal generated by the low voltage system circuit. And a level shift circuit for converting and amplifying the clock pulse of
According to the above configuration, all the components processed by the high voltage system circuit can be gathered immediately before output from the image signal processing from when the image signal is input to when it is applied to the liquid crystal panel. It is possible to perform all of these processes at a low voltage, and power consumption can be suppressed. In addition, since the circuit arranged on the face side can be made smaller than the circuit near the back of the head, the weight balance when the apparatus main body is mounted is good, and the user can work without feeling tired because the wearing deviation does not occur.
[0015]
The head-mounted display device according to claim 4 is characterized in that the high-voltage system circuit further includes frequency conversion means for generating a modulation signal.
[0016]
According to the above configuration, since the number of cables for transmission from the low voltage system circuit to the high voltage system circuit can be further reduced, space efficiency is improved, and a small and compact HMD can be realized.
[0017]
According to a fifth aspect of the present invention, in the head mounted display device, power supplied from an AC power source or an external power source created by an external signal source or a power source such as a battery is supplied to the vicinity of the back of the holding means by an image processing circuit. It further has a power supply circuit for converting into a usable voltage.
[0018]
According to the above configuration, since only a single power needs to be supplied as the power supplied from the outside or the inside, a readily available device such as a general-purpose battery or an AC adapter is used as long as the supply power (voltage) is satisfied. It is possible to provide a versatile HMD. Furthermore, since the power source may be arranged either outside or inside, it is convenient and portable.
[0019]
The head-mounted display device according to claim 6, wherein the power supply circuit has a shield structure, and the power supply circuit and the low voltage system circuit are separately disposed and electrically connected to each other. And
[0020]
According to the above configuration, since the power supply circuit is shielded and the image processing circuit and the power supply circuit are separately arranged, noise from the power supply circuit to the image processing circuit can be suppressed. Furthermore, since electromagnetic waves that may jump out of the apparatus main body can be cut, it is safe for humans and peripheral devices that are weak against weak radio waves such as medical devices and airplanes.
[0021]
The head-mounted display device according to claim 7 is characterized in that an internal battery for supplying power to the image processing circuit is arranged near the side of the holding means.
[0022]
According to the above configuration, the battery is disposed near the side of the head which is relatively close to the center of gravity of the head and has the least amount of protrusion in the HMD, so that the battery required for a long operation time of the system is provided. Even if it is housed in the body, there is little influence on the weight balance at the time of wearing, and a small HMD can be realized. In addition, since a battery is incorporated in the wireless interface, an external power supply cable is not required, so that an HMD having no cable and excellent workability can be realized.
[0023]
The head-mounted display device according to claim 8 has a guide mechanism for moving the internal battery along the holding means.
[0024]
According to the above configuration, the distance to the power supply circuit can be shortened, which is effective as a noise countermeasure. Furthermore, by changing the mounting position according to the size, shape, and weight of the internal battery and according to the shape of the user's head, the mounting balance can be improved and work can be performed without a sense of incongruity.
[0025]
A head-mounted display device according to claim 9, wherein a signal source for inputting an image signal and a synchronization signal for determining a horizontal / vertical display position of the screen, and the signal source and the low voltage system circuit are electrically connected. A connector for connection is arranged near the back of the holding means.
[0026]
According to the above configuration, since the arrangement is along the processing route of the input signal, there is no waste of wiring, and an HMD excellent in space efficiency can be realized. Moreover, safety and workability are improved by arranging the connection connector in the center of the back that does not disturb the user's work most. Furthermore, since the right / left balance of the apparatus main body does not shift, it is possible to suppress the feeling of fatigue caused by the mounting shift.
[0027]
The head-mounted display device according to claim 10, wherein the connector is electrically connected to the low voltage system circuit by at least one relay cable inside the holding means, and is held so that the connection direction of the connector changes. It is characterized by that.
[0028]
According to the above configuration, since the connector is not directly connected to the input circuit, it can move flexibly by the amount of the relay cable according to the input direction of the input cable, and the stress on the connector and the cable can be eliminated. It is safe because there is no fear of poor connection. Even if the user accidentally pulls the cable and the pulling force is applied to the connector, the connector connection direction changes according to the direction of the input cable, and the connector itself can be easily disconnected. It is safe without worrying about being injured.
[0029]
The head-mounted display device according to claim 11 includes a signal source for inputting an image signal and a synchronization signal for determining a horizontal / vertical display position of the screen, and an AC adapter or a battery independent of the signal source. A power source, a connector for electrically connecting the signal source and the low voltage system circuit, a sensor for detecting a connection state of the connector, and a control circuit for controlling power supply,
When the sensor determines that the connector is not connected, the output from the power source is stopped by the control circuit.
[0030]
According to the above configuration, even when the power is not supplied by the same cable as the image / synchronization signal input to the apparatus main body, that is, even when the power source is independent, the image is output even though the connector is disconnected and there is no input signal. Since the processing for preventing the processing circuit from continuing to operate can be performed only by detecting the connection state of the connector, the protection of the internal circuit and the battery life can be maintained for a long time.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0032]
(First form)
1 to 4 show the circuit arrangement and configuration of the head-mounted display device according to the first embodiment of the present invention. FIG. 1 is a schematic external perspective view of the device main body, and FIGS. 2 and 4 are circuit configuration diagrams. FIG. 3 is a timing chart for explaining the frequency conversion means.
[0033]
In FIG. 1, the HMD includes a holding means (1) and an optical unit (8), and is fixed to the head of the user (2). The optical unit (8) includes, for example, an image display element (5) composed of a liquid crystal panel (3) and a backlight (4) for irradiating the liquid crystal panel (3) from the back, a reflection mirror (6), and a magnifying optical It comprises a lens (7) as means, and is fixed to the holding means (1) by hinge means (9). Furthermore, the optical unit (8) is provided with a mechanism capable of moving left and right in the eye width direction according to the user (2), a depression angle adjustment mechanism, and a diopter adjustment mechanism. After the above adjustment, the user (2) can visually recognize the enlarged virtual image formed by the optical unit (8) in the front visual field.
[0034]
The configuration of the optical unit (8) is not limited to the refractive optical system described above, and a reflective optical system or a see-through optical system may be used. Furthermore, only one optical unit (8) may be provided for monocular vision. Further, although not shown in the present embodiment, an adjustment mechanism for adjusting the holding force of the holding means (1) according to the shape and size of the head of the user (2) may be provided.
[0035]
The image processing circuit housed in the apparatus body is composed of a low voltage system circuit (10) and a high voltage system circuit (11), and the low voltage system circuit (10) is located near the center of the back of the holding means (1). The high voltage system circuit (11) is arranged in the optical unit (8), and both circuits are electrically connected to the inside of the holding means (2) passing near the temporal region of the user (2). A transmission cable (12) for connection is provided. In the present embodiment, an example is shown in which the transmission cable (12) is passed through the holding means (1) and arranged separately for left and right for binocular viewing.
[0036]
FIG. 2 illustrates the circuit configuration of the image processing circuit described above.
[0037]
The image information described below is a data image for a computer such as a VGA (video graphic adapter) or S-VGA used in a personal computer or a portable terminal, and its operating frequency is 25 MHz to 30 MHz and an NTSC television. It is faster than the signal (4.3 MHz).
[0038]
The analog RGB image signal (200) input from the signal source (20) is converted into a first image signal (201) subjected to input processing such as buffer amplifier / clamp / gamma correction in the preprocessing circuit (21), An alternating signal (202) with the polarity reversed for driving the liquid crystal panel is generated by the polarity inverting circuit (22) and then input to the frequency conversion means (23) for performing time extension of the polarity inverting signal (202).
[0039]
Here, while the frequency band of the input polarity inversion signal (202) is as high as 25 MHz as described above, the operating frequency of the liquid crystal panel (3) is only a few MHz that is the same as that of the NTSC system television signal. I don't have it now. Therefore, it is necessary to convert the frequency band of the image signal (200) to a level that satisfies the operating frequency of the liquid crystal panel (3), and the frequency conversion means (23) performs the processing.
[0040]
The image signal input to the sample-and-hold circuit constituting the frequency converting means (23) is serial-parallel converted as shown in FIG. 3, and the frequency of the image signal can be equivalently lowered to 1 / n. . This conversion number n is the frequency f of the liquid crystal panel._LCD, Set the image signal operating frequency (DOTCLK) to f_sThen, it is derived from the following equation.
[0041]
n ≧ f_s / F_LCD
For example, DOTCLK = 25 MHz · f_LCDWhen n = 5 MHz, n ≧ 5, and n = 6, which is a multiple of 3, may be set in order to correspond to image signals input in RGB three colors. Similarly, f_LCDIn the case of = 6.25 MHz, it is sufficient if n ≧ 4.
[0042]
The low voltage system circuit (10) that performs all the above processes constitutes an image processing circuit disposed at the back of the holding means (1). Here, if the operating voltage of the low-voltage circuit is set to 5 V or less, the operating voltage of LVDS (Low Voltage Differential Signaling), which has recently been proposed, as well as the voltage levels of TTL, CMOS, etc. that have been conventionally known Because it is comprehensive, it can be used for input from any conceivable signal source.
[0043]
The operating voltage of the liquid crystal panel (3) varies depending on each liquid crystal panel, but it is necessary to apply a high voltage of about 15 V or 25 V due to various problems such as the threshold curve of the liquid crystal, contrast ratio, and transistor characteristics. . Therefore, regarding the high-voltage drive voltage, if the operating voltage of the level shift circuit is set in accordance with each liquid crystal panel, there is no power loss, and any liquid crystal panel can be used. Therefore, a versatile HMD can be realized.
[0044]
Here, the buffer amplifier (24) for amplifying the frequency conversion signal (203) to a voltage level necessary for liquid crystal panel application is used as a high voltage system circuit (11) immediately before outputting the signal to the liquid crystal panel (3). Since the configuration and arrangement are collectively performed, all the previous processing can be performed at a low voltage level, so that power consumption can be suppressed.
[0045]
On the other hand, the synchronization signal (204) is processed by the input buffer (25) and then sent to the PLL circuit (26) for synchronization control to drive the liquid crystal panel (3) by the panel drive basic CLK generation circuit (27). Basic clock (205) is generated. This basic clock (205) is converted into a drive clock (206) for actually driving the liquid crystal panel in the level shift circuit (28), and is applied to the liquid crystal panel in the same manner as the frequency conversion signal (203) described above. Is amplified to a high voltage level.
[0046]
Further, a pulse (207) for driving the backlight (B / L) (4) for irradiating the liquid crystal panel (3) is generated by a B / L pulse generating circuit (29), and combined with B / L ( Perform brightness control in 4).
[0047]
Further, the POWER (208) supplied to the image processing circuit by the signal source (20) or another power source is converted into a driving voltage used in the image processing circuit in the power source circuit (30), and the low voltage system circuit (10 ) And high voltage system circuit (11).
[0048]
FIG. 4 shows that the frequency conversion means (23) for performing the frequency conversion of the image signal (200) in FIG. 2 has been changed from the low voltage system circuit to the high voltage system circuit (11) side. Since the number of cables for transmitting signals to the system circuit is minimized, there is no influence on the holding structure / space for passing the cables through the holding means, and a small and compact HMD can be realized. .
[0049]
According to the present embodiment, the image processing circuit is separately arranged in the back of the head and the optical unit, so that the number of cables for transmission from the low voltage system circuit to the high voltage system circuit can be reduced, and the transmission cable itself is extremely fine. Therefore, the space inside the holding means can be used efficiently, and a small and lightweight HMD can be realized. Furthermore, since the circuits are separated and arranged according to the voltage level, it is possible to prevent noise from being mixed between the respective circuits and to provide a clear display without noise. In addition, by reducing the circuit scale placed on the face side, there is no excessive weight on the face side of the user when the device is mounted, the weight balance is good, and wearing misalignment does not occur, so the user feels tired You can work without it.
[0050]
(Second form)
5 to 8 show a power supply circuit of the head-mounted display device according to the second embodiment of the present invention. FIG. 5 shows a power supply circuit that converts the power supplied from the power source into a voltage used in the image processing circuit. 6 is a layout diagram of the power supply circuit, FIG. 7 is a schematic external perspective view of the apparatus main body containing the internal battery, and FIG. 8 is a schematic external perspective view of the apparatus main body in which the arrangement position of the internal battery is changed. It is. In addition, about the part similar to a 1st form, the same code | symbol is attached | subjected and description is abbreviate | omitted.
[0051]
In FIG. 5 (a), a variable power source (43) composed of an internal battery (41) or an external battery (42) and a fixed power source (45) created by an AC adapter (44) or a signal source (45). The plurality of power sources composed of 46) and the like can be arbitrarily selected by the user according to the use environment. When two or more power sources are connected at one time, one power source is selected by the switching means (47), then converted to a voltage level used in the image processing circuit by the power circuit (30) and output. . Here, an example in which high voltage 15V is output in addition to analog 5V and digital 5V is shown.
[0052]
FIG. 5B illustrates the switching means (47). When the variable power source (43) and the fixed power source (46) are used as power sources, the fixed power source (46) is preferentially used. .
[0053]
Since the voltage supplied from the fixed power source (46) has a fixed voltage value, there is no need to check the voltage value, and the output (210) of the first and circuit (48) for detecting the presence or absence of power Thus, the first SW (49) is controlled to control the power supply.
[0054]
On the other hand, the power supplied from the variable power source (43) is input to the comparator (50) in order to check the fluctuation amount such as the voltage value and the current capacity. Only when it is confirmed that the remaining voltage is equal to or higher than the set value (Vref), the output (211) of the comparator (50) and the output (212) of the second and circuit (51) at the next stage are high. When the presence of the fixed power source (46) is not recognized, that is, when the output (210) of the first and circuit (48) is low, the output (213) of the not circuit (52) becomes high, and the third and Since the output (214) of the circuit (53) becomes high, the second SW (54) is turned on, and power is supplied from the variable power source (43) to the power supply circuit (30).
[0055]
Since the power supply circuit is arranged in the main body of the device as described above, only a single voltage needs to be supplied as power supplied from the outside or inside. Therefore, a general-purpose battery or AC adapter can be used as long as supply power (voltage) is satisfied. A readily available device such as can be used, and a versatile HMD can be provided. Furthermore, since the power source may be arranged either outside or inside, it is convenient and portable.
[0056]
Further, even when the voltage value (+ V) input to the power supply circuit is an arbitrary voltage value, an image processing circuit is provided by first providing a voltage conversion circuit for once converting into a fixed voltage that does not depend on the input voltage in the input stage. Since a circuit for creating an arbitrary voltage required can be constituted by a general-purpose DC / DC converter, it can be easily realized at low cost.
[0057]
FIG. 6 is a diagram for explaining the arrangement of the low voltage system circuit (10) and the power supply circuit (30) arranged near the back of the holding means (1). FIG. 61) and the power circuit board (62) are configured independently of each other, and are electrically coupled to each other by a cable (63) or a flexible flat cable. FIG. 6B shows that each circuit area (low voltage system circuit area is 64-a and power supply circuit area is 64-i) is formed on the same substrate (64), except for the transmission wiring in the boundary area. Separated. In FIG. 6C, the power circuit board (62) is arranged on the upper side and the low voltage system circuit board (61) is arranged on the lower side, so that the depth or width of the circuit scale arranged on the back of the head can be reduced. In the figure, the depth is narrowed. However, in any of FIGS. 6A to 6C, the substrate arrangement method can be arbitrarily changed, and can be arbitrarily arranged according to the shape constituting the holding means.
[0058]
Furthermore, in the power supply circuit (30), the upper part surface of the substrate (62) is shielded by the metal case (65), and the opposite part surface side is formed by a complete solid GND pattern without through holes. Noise can be prevented from entering the image processing circuit, and electromagnetic waves that may jump out of the apparatus main body can be cut. Therefore, it can be safely used for peripheral devices and human bodies that are weak against weak radio waves such as medical devices and airplanes.
[0059]
7 is different from FIG. 1 in that an internal battery (71) is provided in the vicinity of the temporal region of the holding means (1). FIG. 7A is a perspective view when viewed from the side, and FIG. As shown in FIG. 7 (b), in order to ensure an even weight balance between the left and right sides, the internal battery (71) is left and right within the housing (72) provided outside the vicinity of the side of the holding means (1). By setting the electrodes on the electrodes (73), power is supplied to the power supply circuit (30) arranged near the back of the head by the power supply cable (74) running in parallel with the transmission cable (12).
[0060]
FIG. 8 is a diagram illustrating a structure in which the mounting position of the internal battery (71) can be changed to any position along the horizontal direction of the holding means (1). FIG. 8A is a perspective view when viewed from above, and is moved to the back of the head compared to FIG. 7A. Although not shown here, the circuit storage portion (75) for storing the low-voltage circuit (10) and the power supply circuit (30) together may also have a movable structure. In that case, if only one internal battery (71) is housed and arranged on the side opposite to the moving direction of the circuit housing section (75), a weight balance can be achieved.
[0061]
According to the above configuration, the battery is disposed near the side of the head which is relatively close to the center of gravity of the head and has the least amount of protrusion in the HMD, so that the battery required for a long operation time of the system is provided. Even if it is housed in the body, there is little influence on the weight balance at the time of wearing, and a small HMD can be realized. In addition, since a battery is incorporated in the wireless interface, an external power supply cable is not required, so that an HMD having no cable and excellent workability can be realized.
[0062]
FIG. 8B shows the structure of the guide provided in the holding means (1), and the guide support (76) to which the housing (72) containing the internal battery (71) is attached is the guide inside the holding means. It moves along the rail (77). The power cable (74) and the transmission cable (12) are wired along a groove (78) provided on the housing (72) side inside the holding means (1).
[0063]
If the arrangement position of the battery is changed in this way, the distance to the power supply circuit can be shortened, which is effective as a noise countermeasure. Furthermore, by changing the mounting position of the battery according to the size, shape and weight of the internal battery, or according to the shape of the user's head, the mounting balance is further improved and work can be performed without a sense of incongruity.
[0064]
(Third form)
9 and 10 illustrate the interface of the head-mounted display device according to the third embodiment of the present invention, FIG. 9 is a configuration diagram of the input connector, and FIG. 10 controls the power supply according to the connection of the input connector. It is a block diagram of the circuit which performs. In addition, about the part similar to a 1st form, the same code | symbol is attached | subjected and description is abbreviate | omitted.
[0065]
FIG. 9 is a diagram illustrating an input interface between a low-voltage circuit and a signal source arranged at the back of the head illustrated in FIG. 1 or FIG.
[0066]
The input cable (91) for transmitting a signal from the signal source (20) is connected to the male side (a) of the input connector (92), and a circuit storage portion (for storing a circuit arranged at the back of the head) 75) is connected to the female side (A) of the input connector (92) in the vicinity of the connection window provided in the approximate center. The female connector (92-a) is electrically connected to the low voltage system circuit (10) by a relay cable (93), and may be a direct input type as shown in FIG. The input to the circuit (10) may be a connector (95). As shown in FIG. 9B, one end slit (94) may be passed in the middle of the relay cable (93) in order to protect the input part to the low voltage system circuit (10).
[0067]
According to the above configuration, since the arrangement is along the input signal processing route, an HMD excellent in wiring / space efficiency can be realized. In addition, since it is the place that does not disturb the user's work, the safety and workability are improved, the apparatus body has a good left / right / front / back balance, and fatigue due to misalignment can be suppressed as much as possible.
[0068]
Furthermore, since the female side of the input connector is not directly connected to the low-voltage system circuit, it can move flexibly by the length of the relay cable according to the input direction of the input cable, eliminating the stress on the connector and cable. It is safe because there is no fear of poor connection.
[0069]
The connection window (96) provided near the center of the circuit housing (75) is a window with room on the top, bottom, left, and right so that the input cable (91) can follow easily even when it is oriented in any direction. Therefore, even if the user accidentally hooks the cable, the connection direction of the connector changes according to the direction of the input cable, and the connector itself can be detached and cheap. It is safe without worrying about being injured by being pulled.
[0070]
FIG. 10 shows that in the case where the power source (101) is provided independently of the signal input from the signal source (20), it is possible to prevent only power from being supplied despite the absence of the input signal. It is for demonstrating a control system.
[0071]
First, in order to check the input signal from the signal source (20), a sensor (102) is provided at the connection part of the input connector (92), and when the connection is confirmed, the image / synchronization signal is directly sent to the low voltage system. The power supplied from the power source (101) is transmitted to the circuit (10) to the power supply circuit (30), and normal processing is performed. On the other hand, if it is determined that the input connector (92) is not connected, the switch SW (104) is controlled by the control signal (220) created by the control circuit (103), and the power source (101) Stop power supply.
[0072]
The power source (101) described here is the variable power source (43) such as the internal battery (41) and the external battery (42) or the fixed power source (46) as described above. Regardless of which power source (101) is connected, the input voltage value is first checked by the comparator (105), and any power source (101) can be supported by setting the check voltage (Vref). is there. If the output (221) of the comparator (105) and the detection result (222) of the sensor (102) provided in the input connector (92) are input to the AND circuit (106), both inputs are AND unless the input is high. Since the output (220) of the circuit (106) is low and the switch SW (104) is off, the power supply can be reliably stopped in a state where the input connector (92) is not connected.
[0073]
The above power control system can prevent the image processing circuit from continuing to operate even when the connector is disconnected and there is no input signal, just by detecting the input state of the connector. In the case of battery driving, the battery life can be maintained long.
[Brief description of the drawings]
FIGS. 1A and 1B are schematic external views according to a first embodiment of the present invention, in which FIG. 1A is a side perspective view, and FIG.
FIG. 2 is a circuit configuration diagram showing a first embodiment of the present invention.
FIG. 3 is a timing chart for explaining frequency conversion means in the first embodiment of the present invention.
FIG. 4 is a circuit configuration diagram showing a first embodiment of the present invention.
5A and 5B are configuration diagrams of a power supply circuit according to a second embodiment of the present invention, in which FIG. 5A is a circuit block diagram, and FIG. 5B is a configuration diagram of switching means.
FIG. 6 is a layout diagram of a power supply circuit and a low voltage system circuit according to the second embodiment of the present invention.
7A and 7B are schematic external views for explaining storage of an internal battery according to the second embodiment of the present invention, where FIG. 7A is a side perspective view, and FIG. 7B is a perspective view seen from above.
8A and 8B are schematic external views for explaining the arrangement position of the internal battery in the second embodiment of the present invention, in which FIG. 8A is a perspective view seen from above, and FIG. 8B is a cross-sectional view.
9A and 9B are configuration diagrams for explaining an input connector according to a third embodiment of the present invention, in which FIGS. 9A and 9B are side perspective views, and FIG. 9C is a rear view.
FIGS. 10A and 10B are diagrams for explaining a system for controlling power supply according to connection of an input connector according to a third embodiment of the present invention, where FIG. 10A is a circuit block diagram and FIG. 10B is a configuration of a control circuit; Figure.
FIG. 11 is a perspective view showing a wearing state of a conventional head-mounted display device.
FIG. 12 is a cross-sectional view showing an optical unit of a conventional head-mounted display device.
[Explanation of symbols]
1 Holding means
2 users
3 LCD panel
4 Backlight
5 Image display element
6 Mirror
7 Lens
8 Optical unit
9 Hinge
10 Low voltage circuit
11 High voltage circuit
12 transmission cable
20 Signal source
21 Pre-processing circuit
22 Polarity inversion circuit
23 Frequency conversion means
24 Buffer amplifier
25 Sync signal buffer
26 PLL circuit
27 Panel basic CLK generation circuit
28 L / S circuit
29 B / L pulse generation circuit
30 Power supply circuit
41 Internal battery
42 External battery
43 Variable power source
44 AC adapter
45 Signal power
46 Fixed Power Source
47 Switching means
48 1st and circuit
49 1st SW
50 Comparator
51 Second and circuit
52 not circuit
53 Third and circuit
54 Second SW
61 Low-voltage circuit board
62 Power circuit board
63 cable
64 Same circuit board
65 metal case
71 battery
72 Housing
73 electrodes
74 Power cable
75 Circuit storage
76 Guide support
77 Guide rail
78 Groove
91 Input cable
92 Input connector
93 Relay cable
94 slit
95 connector
96 Connection window
101 Power source
102 sensors
103 Control circuit
104 Switch SW
105 Comparator
106 and circuit
200 Image signal
201 First image signal
202 Polarity inversion signal
203 Frequency conversion signal
204 Sync signal
205 Basic clock
206 Drive clock
207 Backlight pulse
208 POWER
210 1st and circuit output
211 Comparator output
212 Second and circuit output
213 not circuit output
214 3rd and circuit output
220 Control signal
221 Comparator output
222 Sensor output
501 Video playback device
502 users
503 HMD with integrated holding means
504 Electric circuit
505 Wiring
506 eaves
507 connector
508 display
511 LCD panel
512 light source
513 lens
514 mirror
515 Enlarged display
516 User's Eye

Claims (11)

An optical unit comprising an image display element and a magnifying optical system for enlarging an image formed by the image display element, holding means for fixing the optical unit in front of the user's head, and an image signal on the image display element In a head-mounted display device configured with an image processing circuit that performs processing for displaying
In the image processing circuit, a low voltage system circuit is separately disposed near the back of the holding means, and a high voltage system circuit is separately disposed in the optical unit, and the low voltage system circuit and the high voltage system circuit are electrically connected to each other. A head-mounted display device characterized by that. In the low voltage system circuit, a driving voltage for processing the image signal input from a signal source and a synchronization signal for determining a horizontal / vertical display position of a screen is 5 V or less, and the high voltage system circuit includes: The head-mounted display device according to claim 1, wherein the head-mounted display device is a circuit that is processed by a voltage other than the low-voltage circuit, that is, a drive voltage of 5 V or more. The high voltage system circuit converts and amplifies a clock amplifier for driving the liquid crystal panel and a buffer amplifier for amplifying the time-expanded modulation signal of the image signal created by the low voltage system circuit The head-mounted display device according to claim 1, comprising: a level shift circuit. 4. The head-mounted display device according to claim 3, wherein the high voltage system circuit further includes frequency conversion means for generating the modulation signal. Near the back of the holding means, an external power source created by an AC adapter or an external signal source, or a power circuit for converting power supplied from a power source such as a battery into a voltage usable by the image processing circuit The head-mounted display device according to claim 1, further comprising: 6. The head mounted device according to claim 5, wherein the power supply circuit has a shield structure, and the power supply circuit and the low voltage system circuit are separately disposed and electrically connected to each other. Type display device. The head-mounted display device according to claim 1, wherein an internal battery for supplying power to the image processing circuit is disposed near a side of the holding unit. The head-mounted display device according to claim 7, further comprising a guide mechanism for moving the internal battery along the holding unit. A signal source for inputting the image signal and a synchronization signal for determining a horizontal / vertical display position of the screen, and a connector for electrically connecting the signal source and the low voltage system circuit are provided on the holding means. The head-mounted display device according to claim 1, wherein the head-mounted display device is disposed near the back of the head. 10. The connector according to claim 9, wherein the connector is electrically connected to the low-voltage circuit by at least one relay cable inside the holding means and the connection direction of the connector is changed. The head-mounted display device described in 1. A signal source for inputting the image signal and a synchronization signal for determining a horizontal / vertical display position of the screen, a power source such as an AC adapter or a battery independent of the signal source, the signal source and the low voltage system A connector for electrically connecting the circuit, a sensor for detecting a connection state of the connector, and a control circuit for controlling power supply;
The head-mounted display device according to claim 1, wherein when the sensor determines that the connector is in a disconnected state, output from the power source is stopped by the control circuit.

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