JPS63142341A - Projection display device - Google Patents

Abstract

PURPOSE:To project a large amount of display information and to facilitate information selection and display operation by using a liquid crystal plate as an information sheet where an image is projected, adjusting the illuminance of projection light, and switching projection on a screen and a display only on the surface of the liquid crystal plate. CONSTITUTION:Information read out of a floppy disk 221 is converted by a display control part 223 into a control signal of the liquid crystal plate 22 and the signal is supplied to the liquid crystal plate 22. A projection lamp 24 is connected to a power unit 26 and supplied with a source voltage through the switching of contacts of a switch 28 or through the voltage is lowered to a low voltage through a dimming circuit 27. Then when the dimming circuit 27 is inserted, the display is so controlled that it is seen only on the liquid crystal plate 22. Therefore, an image is displayed only on the liquid crystal plate 22 and not projected on the screen to prevent a viewer from sensing the display contents. Further, when remote control transmitter 281 and a remote control receiver 282 are used, the switch 28 is put in operation to easily switch the projection display on the screen 25 and the display only on the liquid crystal plate 22.

Description

[Detailed Description of the Invention] [Summary] In a projection display device that uses reflected light, a liquid crystal panel is used as an information sheet to be projected, and the illuminance of the projected light is adjusted.
It is possible to switch between projection onto the slurry and displaying only the screen on the liquid crystal panel.

[Industrial application field]

The present invention relates to improvements in projection display devices.

A display device that records characters, figures, etc. on a transparent sheet, collects the transmitted light from the back of the sheet with a condensing lens, and projects it onto a screen is called an overhead projector, and is a means of visually transmitting all information. It is used as A.

When using such a projection display device, it is desirable to prepare a sufficient number of sheets with sufficient information content to serve as an information source, and the device itself should be easy to handle for the operator. is desirable.

[Conventional technology]

In a conventional projection display device, information to be transmitted is recorded and held on a transparent sheet 2, as shown in FIG.

The sheet 2 is placed on a transparent substrate 3 as shown in the figure, and the projection lamp 4 to which a current is supplied from the source device 6 is made to emit light, and the light and sound condensing lens 1 is used to collect the light, and the sheet 2 is placed on the transparent substrate 3. Irradiates uniformly from the back side.

The transmitted light of the sheet 2 is opposite to the condensing lens 9! Boku 7 completes the projection onto the screen, and the information on the sheet is projected.

The screen on the screen 5 is changed by replacing the sheet 2.

When replacing, it is necessary to select the sheet and confirm the contents.

On the other hand, in some cases, it is desirable to be able to display related information, such as explanatory materials, in a way that only the operator can understand, without the viewer knowing. At this time, by providing a written part on a part of the information sheet 2 used by the operator, for example, in the periphery of the sheet, this written part can be directly felt by the viewer when the sheet is projected. It is used without any problem.

Note that the switch 8 in the figure is used for blinking the projection lamp.

[Invention is y! 4 Problems to be resolved] With the conventional FT as described above, when there are many sheets to project, replacing sheets is complicated, and when sheets are used with irregular titles,
Selection and confirmation are not easy.

In addition, if related materials are used without being projected onto the screen 11, they should be made into separate and independent materials on the sheet, or even if they are written on a part of the sheet, the projected light of that part should be blocked. There is a serious problem in that it requires a lot of effort and effort to prevent viewers from perceiving this by taking measures such as the following.

[Means for solving problems]

Considering the above problem, as shown in the principle diagram of the present invention in Figure 1,
A liquid crystal plate equipped with a reflective mirror 13 on the back surface 2, a projection lamp 14 that illuminates the liquid crystal panel, and a projection lamp 14 that supplies an electric current to the projection lamp to project the information displayed on the liquid crystal plate onto a screen 5 and attenuate the light. The circuit 17 is inserted and the display function is performed on the liquid crystal plate 1.
I can keep it on 2! This problem is solved by the projection display device of the present invention, which includes a source device itt16.

[Effect]

According to the present invention, the 12 liquid crystal plates play the role of transparent sheets, and the displayed information can be easily changed by electrical input from the outside of the 2 liquid crystal plates. In addition, a reflector 13 provided on the back side of the liquid crystal panel 12 allows the reflected light of the projection lamp 14 emitted from the front side of the liquid crystal plate 12 to pass through the liquid crystal plate 12 and be projected onto the screen. By controlling the current supplied to the lamp 14, it is possible to display only a logical image on the liquid crystal panel 12, so that the projection on the screen is in an I/-1 manner that is imperceptible to the viewer.

〔Example〕

The illustrated embodiments will be described in detail below.

Figure 2 is a block circuit diagram of a projection display device according to an embodiment of the present invention.

As you can see in the figure, 22 is a liquid crystal panel, 24 projection lamps, and 25 screens.

The liquid crystal gi 22 reflects the projection light from the projection lamp 24 and displays the information on the liquid crystal plate 22 on the screen 25.

The information displayed on the liquid crystal panel 22 is displayed on a floppy disk 2, for example.
21. Floppy disk reading section 222F
By inputting the i read command, the necessary storage information is retrieved from the floppy disk 221. This extracted information is converted into a liquid crystal plate 220 control signal by the display control unit 223 and is applied to the liquid crystal plate 22. The projection unit 24 is connected to a power supply 26, and by switching the contacts of a switch 28, the VT source voltage can be supplied directly or it can be reduced to a low voltage through a dimming circuit 27 consisting of a resistor circuit. . When the dimming circuit 27 is inserted, the display is controlled so that only a portion of the display is visible on the liquid crystal panel 22.

For example, a phase change type liquid crystal with high light transmittance can be used for the liquid crystal plate 22 used in the present invention.

Display control information is stored on a floppy disk, and all required data is continuously displayed on the liquid crystal panel 22 as needed.

A 70-tube disk can store a large amount of display information, and in this case, lists necessary for information selection and other information-related materials can also be stored on the floppy disk.

When using these data, a dimming circuit 27 is inserted into the power supply 26, and the display is displayed only on the liquid crystal panel 22, without being projected on the screen, so that the displayed content is uniformly displayed so that it is not perceptible to the viewer. I can do it.

By using the remote control transmitter 281 and the remote control receiver 282, the switch 28 can easily switch between the projection display on the screen 25 and the display only on the liquid crystal panel 22.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to project a large amount of display information, to facilitate information selection and display operation, and to use the liquid crystal panel for projection as a display section for operating the display device. shall be. In addition, the structure of the display device is simple and compact, and its effects #'i are extremely large.

[Brief explanation of the drawing]

FIG. 1 is a principle diagram of the present invention, FIG. 2 is a block circuit diagram of a projection display device according to an embodiment of the present invention, and FIG. 3 is a block diagram of a conventional projection display device. As shown in the figure, 1.1] is a lens, 2 is a sheet, 3 is a transparent substrate, 4.14.24 is a projection lamp, 5.15.25 is a screen, 6.16.26a [source device, 7.13 .20, 30 reflector, 8.18.28 switch, 9.19.29 condenser lens, 12.22 Fi liquid crystal panel, 223 display control unit, 281 remote control transmitter, 282 remote control It is a receiver. Reference diagram of the principle of the invention $1 diagram

Claims (1)

[Claims] A liquid crystal plate (12) with a reflective mirror (13) on the back side, a projection lamp (14) that illuminates the liquid crystal surface, and a current is supplied to the projection lamp to display information displayed on the liquid crystal plate on the screen (1).
5) A power supply device (1) that displays images only on the liquid crystal panel (12) when the dimming circuit (17) is inserted.
6) A projection display device comprising: