JPH0530849U - Desktop display - Google Patents

Abstract

(57) [Summary] [Structure] The projection screen 1 provided on the top surface 20 of the desk.
1 and 11, a transmissive liquid crystal panel 12 provided in a position parallel to 11 above 11, and a projection lens 13 for connecting the image of 12 to 11
, A planar light source 14 that illuminates 12 from the rear, a condenser lens 15 that connects the image of 14 to 13 and 12, 13, 14, 1
It has a support mechanism 16 for supporting 5, a power supply circuit 23, and an interface circuit 24. 13 optical axis is 12
Pass one point on one side. 14 is provided separately, and the light guide tube 2
2 guides light. [Effect] The space occupied on the desk is small. Little operator eye strain. There is no problem such as lighting behind the operator. It is easy to move when using and not using. The size or projection position of the display screen can be changed as needed. The problem of image distortion does not occur. No shadow can be created by the operator's body. There is no pressure on the work environment.
Does not require heat resistance. The mobility and operability of the device are excellent.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a peripheral device for a computer, and more particularly to a display device for displaying the work content of a host computer in real time.

[0002]

[Prior Art]

 Conventionally, as a desk-top display device, that is, a display device used on an office desk or the like, there is, for example, a CRT display using a 14-inch cathode ray tube.

Further, in recent years, with the progress of development of flat panel display devices, liquid crystal displays, plasma displays and the like have come to be used for so-called laptop personal computers and the like, and have become popular as desk-top display devices.

On the other hand, a liquid crystal projector that projects a screen of a liquid crystal panel onto a wall surface or the like has come to be used for the purpose of realizing a large screen television.

[0005]

[Problems to be solved by the device]

 Among the conventional desk-top display devices described above, the CRT display occupies a large part of the space on the desk and is heavy, which is an obstacle when not in use.

[0006] In that respect, a laptop personal computer or a so-called notebook personal computer is not as heavy as a CRT display, so it is possible to move to a place a little far from the hand when not in use, but it is still a few. It weighs a kilogram and is not so easy to move. There is also the problem of occupying a desk space of about A4 size. Furthermore, there is a limit of about 1 cm to make a thin display device.

Further, as a drawback that a CRT display and a liquid crystal display and the like have in common, it is that eye fatigue is caused by long-term use, and that the illumination or the like behind the operator is reflected on the display screen. There are also problems. The size of the screen is fixed to the size decided at the design stage regardless of whether it is a CRT display or a liquid crystal display, and it cannot be changed as needed during use.

On the other hand, if a liquid crystal projector is used with the upper surface of the desk as the projection surface, all of the above problems can be solved, but if the projector is installed directly above the desk, it will be shaded by the operator's body or the like. There is a problem that the image is distorted if the image is projected obliquely from above in order to avoid it.

An object of the present invention is a display device such as a lighting device which is positioned diagonally above an office desk, etc., and occupies a small space on the desk even when it is not in use, and causes eye fatigue, glare, and images. It is an object of the present invention to provide a desk-top display device that can change the size and projection position of the display screen as necessary without the problem of distortion.

[0010]

[Means for Solving the Problems]

 In order to achieve the above object, a desk-top display device of the present invention comprises a projection screen provided on a horizontal plane such as the top surface of a desk, and a transmission screen arranged above the projection screen which is optically parallel to the projection screen. Type liquid crystal panel, and a projection lens positioned between them so that an image on the display surface of the transmissive liquid crystal panel is formed on the surface of the projection screen and having an optical axis perpendicular to both surfaces thereof. A planar light source that illuminates the transmissive liquid crystal panel from behind, and a planar light source that is positioned between them so that an image of the planar light source is formed at the position of the projection lens, and is perpendicular to both surfaces thereof. A condensing lens having an optical axis, a supporting mechanism for supporting the positional relationship of each of the above-mentioned members as described above, an interface circuit for receiving display content data from a host computer and supplying the data to the transmissive liquid crystal panel, Is made of the power the power supply circuit that to supply to each of the over-mold the liquid crystal panel and the planar light source.

Further, when the display surface of the transmissive liquid crystal panel is regarded as a rectangle, it is effective to use a perpendicular line that stands on the display surface at one point on one side as the optical axis of the projection lens. is there.

Further, one end of a light guide tube made of an optical fiber or the like may be arranged at the position of the planar light source, and the light source may be provided at the other end of the light guide tube.

[0013]

[Action]

 The desk-top display device configured as described above does not get in the way even when it is not used, the projection is not obstructed by the operator's body, the distortion of the image formed on the projection screen is small, and the host computer etc. Works to display the output screen of.

In addition, it works so that the eyestrain and the illumination behind the operator are not reflected.

Furthermore, it works so that the size and projection position of the screen can be changed as necessary.

[0016]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic view showing a first embodiment of the present invention. The tabletop display device according to the present invention is literally used by being placed on the top surface 20 of a desk or the like, but the projection screen 11 and the support 19 directly contact the desktop. The projection screen 11 is a flat sheet made of a highly reflective material, and it is possible to project even if it is not placed on the top surface 20 of the desk. It has the advantages of being clearly visible and being able to check the display range.

A power supply circuit 23 and an interface circuit 24 are provided in the housing of the support base 19. The power supply circuit 23 is a circuit that converts an AC voltage of, for example, 100 V, which is available in an office environment, into a DC voltage of about 10 V. The obtained DC voltage is sent to each of the flat light source 14 and the transmissive liquid crystal panel 12 via the cable 18, but the light amount of the flat light source 14 can usually be adjusted by changing the applied voltage. Therefore, it is desirable that the power supply circuit 23 be capable of adjusting the output voltage. In that case, since the voltage supplied to the transmissive liquid crystal panel 12 is constant, two types of power supplies are required via the cable 18.

The interface circuit 24 is a circuit that receives the display content data transferred from the host computer, converts it into a form used in the transmissive liquid crystal panel 12, and sends it out. When a so-called liquid crystal controller is directly connected to the bus of the host computer and provided in the housing of the host computer, the signal sent from the host computer becomes the liquid crystal control signal, and thus the interface circuit 24 is transferred. It consists of a relatively simple circuit consisting of a buffer for receiving signals and a decompression circuit for decompressing a compressed signal. When the signal sent from the host computer is a so-called RGB signal, the interface circuit 24 needs to include a video RAM and a so-called liquid crystal controller.

The support arm 17 is a member whose one end is mechanically connected to the support base 19 and the other end is mechanically connected to the support mechanism 16. The support arm 17 and the planar shape supported by the support mechanism 16 are provided. The light source 14, the condenser lens 15, the transmissive liquid crystal panel 12, the projection lens 13 and the like are made of a material having sufficient strength to support the weight. For example, a tubular body formed by spirally winding strip-shaped steel (hereinafter abbreviated as "flexible supporting arm") can be used as the supporting arm. In that case, the height and direction of the support mechanism 16 from the upper surface 20 of the desk can be freely changed, and the support mechanism 16 can be supported at an arbitrary position. This is an advantage that the support mechanism 16 is held at a position slightly far from the operator when not in use, and it is easy to pull it up and use it only when in use, and it is possible to change the size or projection position of the projection screen. Is advantageous in that

A cable 18 is provided inside or outside the support arm 17 and along the same. In addition to the above-mentioned two types of power sources, control signals for controlling the transmissive liquid crystal panel 12 and display content data are transmitted and received via the cable 18. In the figure, the cable 18 is drawn as if it consists of two signal lines, but since the liquid crystal display content data is generally 8 bits or 16 bits, the actual cable 18 is about a dozen or so. It is composed of the signal line of.

The planar light source 14, the condensing lens 15, the transmissive liquid crystal panel 12, the projection lens 13, etc., which are supported by the support mechanism 16 and maintain a positional relationship, are an optical instrument generally known as a liquid crystal projector. The screen of the transmissive liquid crystal panel 12 is projected on the projection screen 11 by being arranged according to the same principle as an optical instrument known as a slide projector or a magic lamp. To briefly explain the positional relationship, the condenser lens 15 forms an image of the planar light source 14 on the projection lens 13, and the projection lens 13 forms the image of the transmissive liquid crystal panel 12 on the projection screen 11. It is arranged so as to form an image, and its specific numerical value is determined by an imaging formula well known in geometric optics. The transmissive liquid crystal panel 12 is placed in the immediate vicinity of the condenser lens 15, and the entire surface thereof is irradiated with the light of the planar light source 14. Although not shown in the figure, when the flexible support arm described above is used as the support arm 17, the height of the support mechanism 16 with respect to the top surface 20 of the desk is variable, so that the projection is performed on the projection screen 11. It is desirable to provide an adjusting mechanism for adjusting the position of the projection lens 13 for adjusting the image pint.

A halogen lamp, for example, can be used as the planar light source 14. There are various types of lamps with a life span of about 50 hours to about 2000 hours that are commercially available, and many of them are used by applying a DC voltage of several volts to ten and several volts. It goes without saying that it is preferable to provide a lamp replacement mechanism at an appropriate position of the support mechanism 16.

As the transmissive liquid crystal panel 12, the one used in a normal liquid crystal projector or the like can be used as it is. For example, a 1.4 type, that is, a diagonal length of 1.4 inches can be used. Considering that the size of the projection screen 11 is smaller than the top surface 20 of the desk, that is, at most about 10 inches, the resolution is as high as that used for a liquid crystal projector for large screen projection. Does not need to be. This is advantageous in providing a low-cost desktop display device.

FIG. 2 is a schematic view showing a second embodiment of the present invention. Most of the points are similar to those of the above-mentioned first embodiment, but the feature is that the way of setting the optical axis is devised. That is, when the display surface of the transmissive liquid crystal panel 12 is regarded as a rectangle, a perpendicular line standing at one point on one side of the display surface is the optical axis 21 of the projection lens. At this time, the optical axis 21 of the projection lens simultaneously becomes a perpendicular line standing on the projection plane at one point on one side of the projection screen 11. It goes without saying that a rectangular vertex can be selected as a point on the above side.

In this embodiment, the harmful effect of the first embodiment, that is, the support mechanism 16 is located right above the projection screen, causes a shadow due to the operator's body, and creates a feeling of pressure in the working environment. This is effective when trying to project from diagonally above in order to remove such things. If projection is performed only obliquely, it is possible to change the orientation of the support mechanism 16 by using the flexible support arm in the first embodiment. In that case, the transmissive liquid crystal panel 12 is projected onto the projection screen 11. The distortion of the image is large because it is no longer parallel. In order to solve the problem, the above-mentioned optical axis is taken in this embodiment. Due to this way of taking the optical axis, there is little distortion of the image, and it is possible to obtain a good image that is well-focused on the whole. For example, when trying to take a picture of a printed matter on a wall with a camera in daily life It can be learned from the experience that good results can be obtained by taking the above angle even when the angle standing right in front of the angle cannot be taken.

In the present embodiment, at the same time, the positional relationship between the planar light source 14 and the projection lens 13 and the way of setting the optical axis of the condenser lens 15 are shown in FIG. It should be different from the example. This is because it is necessary for the light from the planar light source 14 to illuminate the transmissive liquid crystal panel 12 without waste and to form an image of the planar light source 14 on the projection lens 13.

FIG. 3 is a schematic view showing a third embodiment of the present invention. The feature of this embodiment is that the planar light source 14 is not provided on the support mechanism 16 side but is provided inside the housing of the support base 19. The light emitted from the planar light source 14 is guided to near the condenser lens 15 on the support mechanism 16 side through the light guide tube 22 provided in the support arm 17. As the light guide tube 22, for example, a so-called optical fiber made of an optical material such as plastic or glass can be used. Even when the above-mentioned flexible support arm is used as the support arm 17, by using a bundle of a plurality of optical fibers which are not adhered to each other, the property of being freely bendable is not lost.

According to the present embodiment, the weight on the side of the support mechanism 16 is reduced in two senses. First, by not providing a lamp such as a halogen lamp on the support mechanism 16 side, not only the lamp but also the lamp replacement mechanism becomes unnecessary. Secondly, since the light guided by the light guide tube 22 is light without heat, it is not necessary for each member on the support mechanism side to be heat resistant. This increases the mobility on the side of the support mechanism 16 and, in turn, improves the operability. Further, since the flat light source 14 is provided on the support base 19 side, a cooling fan can be provided if necessary.

Although the above description has been made on the premise of use in an office environment such as an office desk, that is, OA, a display device for displaying an assembly manual to a worker in, for example, an assembly process in a factory. It goes without saying that it can also be used for FA purposes such as use as. Also, although the description has been given assuming that the output device is a computer, it is possible to use the device according to the present invention as an output device for a television or video, or to have both computer output and television or video output. I am hungry.

[0030]

EFFECTS OF THE INVENTION Since the tabletop display device according to the present invention is configured as described above, it has the following effects. Since the support base, the support arm, and the support mechanism are configured as described above, the space occupied on the desk is small. Little operator eye strain. There is no problem such as lighting behind the operator.

Further, by making the support arm flexible, it is possible to easily move the arm during use and when not in use, and the size or projection position of the display screen can be changed as necessary.

Further, by devising the way of arranging the optical axis, the problem of image distortion does not occur even when the projection lens or the like is positioned diagonally above, and the shadow due to the operator's body or the like cannot be generated, and the work environment is reduced. There is no sense of pressure.

Further, by using the light guide tube, heat resistance of the liquid crystal panel and the like is not required, and the mobility and operability of the device are improved.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing a second embodiment of the present invention.

FIG. 3 is a schematic diagram showing a third embodiment of the present invention.

[Explanation of symbols]

 11 Projection Screen 12 Transmissive Liquid Crystal Panel 13 Projection Lens 14 Planar Light Source 15 Condenser Lens 16 Support Mechanism 17 Support Arm 18 Cable 19 Support Stand 20 Desk Top Surface 21 Projection Lens Optical Axis 22 Light Guide Tube 23 Power Supply Circuit 24 Interface Circuit

Claims (3)

[Scope of utility model registration request] 1. A projection screen provided on a horizontal plane such as an upper surface of a desk, a transmissive liquid crystal panel disposed above and in a position optically parallel to the projection screen, and a transmissive liquid crystal panel comprising: A projection lens positioned between them so that an image of the display surface is formed on the surface of the projection screen and having an optical axis perpendicular to both surfaces thereof; and a plane for irradiating the transmissive liquid crystal panel from behind. Light source, a condensing lens positioned between them so that an image of the planar light source is formed at the position of the projection lens, and having an optical axis perpendicular to both surfaces thereof; A support mechanism for supporting the positional relationship of the above as described above, an interface circuit that receives display content data from a host computer and supplies the display content data to the transmissive liquid crystal panel, the transmissive liquid crystal panel and the planar light source. Tabletop display device consisting of a power supply circuit for supplying power to each. 2. When the display surface of the transmissive liquid crystal panel is regarded as a rectangle, a perpendicular line which stands on the display surface at one point on one side thereof is used as the optical axis of the projection lens. The desktop display device according to claim 1. 3. The tabletop according to claim 1, wherein one end of a light guide tube made of an optical fiber or the like is arranged at the position of the planar light source, and a light source is provided at the other end of the light guide tube. Display device.