JPH04181938A - Projection type display device - Google Patents

Abstract

PURPOSE:To make the optical axis of an image projected from a device to coincide with the prescribed position of a screen regardless of the position of the screen by providing a freely turnable reflecting mirror which can carry out adjustment from the outside of a device frame body, inside the device frame body between a reflecting lens and the screen. CONSTITUTION:The reflecting mirrors 12 and 16 provided inside the device frame body 11 between the projecting lens 8 and the screen 9, and a means adjusting an installing angle with respect to the optical axis of the variable reflecting mirror 16 out of them, from the outside of the device frame body 11, are provided. A constitution is adopted so that he freely turnable reflecting mirror which can adjust the installing angle with respect to the optical axis from the outside of the device frame body is provided between the projecting lens inside the device frame body and the screen. Therefore, the projecting angle of an image projected from the device on the screen, can be adjusted, and the device can be installed even at any positions of a projecting room regardless of the position of the screen.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a projection type display device that can be installed in any location.

[Prior Art] FIG. 7 is a principle diagram showing a conventional projection display device disclosed in, for example, Japanese Patent Laid-Open No. 63-247720. In the figure, 1 is a light source such as a halogen lamp having a reflecting mirror 2;
4a and 4b are condenser lenses, and an infrared filter 3 is installed between them. Reference numeral 6 denotes a polarizing panel, in front of which are installed quick lock mirrors 5a and 5b for color separation, dichroic mirrors 5c and 5d for color synthesis, and total reflection mirrors 10a and Job, each at a predetermined angle. On the other hand, the color separation dichroic mirror 5
Transmissive liquid crystal panels 7a, 7b, 7c are arranged on the optical path of the light separated by colors a and 5b to receive each light.
is located. Reference numeral 8 denotes a projection lens, and 9 a screen located outside the projection type display device on which an image enlarged and projected from the projection lens 8 is projected.

Next, the operation will be explained. Each transmission type liquid crystal panel 7a,
Monochrome images are formed on 7b and 7c by electrical signals. Now, the white light emitted from the light source 1 passes directly or after being reflected by the reflecting mirror 2, passes through the condenser lens 4a, the infrared filter 3 removes the heat rays of the white light, and then the condenser lens 4b and the polarizing panel 6 and enters the first dichroic mirror 58 for light separation. Here, only the red light is reflected, and the blue and green lights are transmitted and enter the second dichroic mirror 5b, but here, only the blue light is reflected and the green light is transmitted. This green light that has passed enters the transmissive liquid crystal panel 7c, obtains a monochrome image formed on the transmissive liquid crystal panel 7C as green image information, and proceeds to the total reflection mirror 10a.
After being reflected at a right angle by the dichroic mirror 5d for color synthesis, the light is reflected again at a right angle and enters the projection lens 8.

On the other hand, the red light reflected by the color separation dichroic mirror 5a is changed in its traveling direction to a right angle by the total reflection mirror lOb, and is incident on the transmissive liquid crystal panel 7a. The monochrome image is obtained as red image information and is advanced, and is transmitted through dichroic mirrors 5c and 5d for color synthesis to enter the projection lens 8. Similarly, the blue light reflected by the color separation dichroic mirror 5b also enters the transmission type liquid crystal panel 7b like the red light and green light, and is reflected at right angles by the color synthesis dichroic mirror 50 as blue image information. Dichroic mirror 5d for color synthesis
and enters the projection lens 8.

In this way, the image information of the three primary colors of red, blue, and green is transmitted or reflected through the color compositing dichroic mirrors 5c and 5d and combined to form a color image, which is then magnified by the projection lens 8. and is projected on screen 9.

In a conventional apparatus having such a configuration, a method as shown in FIG. 8, for example, was used to shift the projection position of a color image on the screen. In other words, in the figure, when attempting to adjust the projection position to the height X from the floor 27 to the screen 9, the mounts 26a and 26b of appropriate heights are stacked to the required height, and the projection display device 25 is placed on top of them. It was installed.

[Problems to be Solved by the Invention] Since the conventional projection display device is configured as described above, the optical axis of the image emitted from the device is aligned with a predetermined position on the top, bottom, left and right of the screen 9. There are problems in that not only the device must be installed at a certain height, which limits the installation position of the device, but also mounts 26a and 26b are required depending on the height at which the device is installed.

This invention was made in order to solve the above-mentioned problems, and provides a projection display device that can align the optical axis of an image projected from the device to a predetermined position on the screen, regardless of the position of the screen. The purpose is to obtain.

[Means for Solving the Problems] A projection type display device according to the present invention includes a rotatable reflecting mirror that can be adjusted from outside the device casing inside the device casing between the projection lens and the screen. .

[Operation] The projection type display device according to the present invention can change the projection angle of an image projected with respect to the optical axis using a projection lens that can be rotated and adjusted from outside the device housing.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a principle diagram of a projection type display device showing an embodiment of the present invention, in which 1 to 1 are the same as the conventional device described above. 12 is a total reflection fixed projection mirror; are variable projection mirrors, both of which are installed in front of the projection lens 8 inside the housing IJ. Figures 2 and 3 show detailed views of the fixed projection mirror 12 and the variable projection mirror 16.
In this figure, a fixed projection mirror 12 in which a total reflection mirror J4 is attached to a mirror holder 13 in front of a projection lens 8 is attached to a housing 11 with screws 15 at a predetermined angle. Further, a total reflection mirror 1 is provided near the projection aperture 11a of the housing 11.
7 is a variable projection mirror 16 attached to a mirror holder 18 with a mirror holding plate 19 and attachment screws 20, and this variable projection mirror 16 is attached to the housing 11 so as to be rotatable about a support shaft 18a. ing. 21 is an adjustment knob for adjusting the installation angle with respect to the optical axis of the variable projection mirror 16 provided protruding from the outside of the housing 11, and a gear 21a is formed on the inside thereof, that is, on the inside of the housing. A link member 22 having a gear portion 22a that meshes with a gear 21a is attached to be rotatable about a rotating shaft 23 fixed to the housing 11.
Elongated holes 22c are formed in the arm portions 22b at both ends of the mirror holder 2 to fit into convex portions 18b formed at both ends of the mirror holder 18. A compression spring 24 is attached to the support shaft 18a so as to press the side surface of the mirror holder 18 from both sides thereof.

Next, the operation will be explained. Image information that is a composite of three primary color images of red, blue and green that enters the projection lens 8 through the same path as in the conventional device, exits the projection lens 8 and is reflected at right angles by the fixed projection mirror 12 located beyond it. Further, the moving direction is changed by the movable projection mirror 16, and the projection opening 11 of the housing 11 is
It is emitted from a and projects a color image on the screen 9.

Here, the mirror holder 18 that holds the total reflection mirror 17 near the projection aperture 11a is rotatable around a support shaft 18a provided at the center thereof, and is rotated by an adjustment knob on the outside of the housing 11. 21, the link member 22, which has a gear part 22a that meshes with the gear 21a coaxial with the adjustment knob 21, rotates around the rotating shaft 23, and is engaged with the arm part 22b of the link member 22. By moving the convex portion 18b of the mirror holder 18 that is fitted with the elongated portion 22c, the mirror holder 18 is moved to the support shaft 1.
8a, the installation angle of the total reflection mirror 17 with respect to the optical axis changes as shown by the dashed line in FIG. 3, and the projection angle can be changed.

On the other hand, since both sides of the mirror holder 18 are pressed by the compression springs 24 attached to the support shaft 8a of the mirror holder 18, the mirror holder 18 will remain stable even if vibrations or other external forces are applied to the device. It is not supposed to move.

In the above embodiment, three transmissive liquid crystal panels 7a, 7
Using dichroic mirrors 5a, 5b, 5c, and 5d, the white light emitted from the light source is separated and combined into three colors of red, red, and green using the dichroic mirrors 5a, 5b, 5c, and 5d.
3.17 was used to determine the optical axis angle of the synthesized image light, but even if one color liquid crystal panel 7 is used as shown in FIG. 4, the angle as shown in FIG. The same effect can be expected even if only one variable total reflection mirror 16 is provided at the tip of the projection lens.

Further, as shown in FIG. 6, by arranging the variable total reflection mirror 16 in the lateral direction, the image projected from the projection aperture 11a can be moved in the lateral direction. Furthermore, by making the variable total reflection mirror 16 variable in both the vertical and horizontal directions, the image can be moved in all directions.

[Effects of the Invention] As described above, according to the present invention, there is provided a rotatable reflection mirror between the projection lens and the screen inside the device casing, the installation angle of which can be adjusted with respect to the optical axis from the outside of the device casing. Since the apparatus is configured to include the above, the projection angle of the image projected from the apparatus onto the screen can be adjusted, and the apparatus can be installed at any position in the room where the image is projected, regardless of the position of the screen.

[Brief explanation of drawings]

FIGS. 1, 2, and 3 are a principle diagram, an actual perspective view, and a sectional view of a projection type display device according to an embodiment of the present invention, and FIGS. FIG. 7 is a principle diagram showing a conventional projection display device, and FIG. 8 is a side view showing a method of installing a conventional projection display device. In the figure, 1 is a light source, 7a, 7b, and 7c are transmissive liquid crystal panels, 8 is a projection lens, 9 is a screen, 11 is a housing, 12 is a fixed projection mirror, and 16 is a variable projection mirror. In each figure, the same reference numerals indicate the same or corresponding parts. 2nd Figure 11: Housing 17: Total reflection mirror
21a: @Single 11a: Projection opening 18: Mirror holder 22: Link member 12: Fixed projection mirror 18a: Support shaft 22a: Gear part 1
3: Fully inverted mirror 18b: Convex portion
22b=arm part 14: mirror holder 19:
Mirror holding plate 22C: Long hole 15: Screw
20: Mounting screw 23: Rotating shaft 16:
Variable projection mirror 21: Adjustment knob 24
:Compression spring Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Procedural amendment (voluntary) April 21, 1991 Old 2 Title of the invention Projection type display device 3 Relationship with the person making the amendment Patent application Address 2-2-3 Marunouchi, Chiyoda-ku, Tokyo Address Inside Mitsubishi Electric Corporation, 2-2-3 Marunouchi, Chiyoda-ku, Tokyo ---7 Name (7375) Patent attorney Masuo Oiwa ---
(Note Frame: Shizuka Shizuka) (Contact information: 03:3213) 3421 Patent Department) 5. Detailed description of the invention in the specification to be amended and drawings 6. Contents of the amendment (1) ``On the optical path of light'' on page 2, line 11 of the specification is changed to ``
Correct J on the optical path. (2) “After being reflected,” on page 2 of the specification, lines 19-20,
” should be corrected as “reflected.” (3) [Pass through] on page 3, line 7 of the specification. Correct ``passed through'' to ``transmit.transparent''. (4) In the third line of page 4 of the specification, "same as colored light" is corrected to "like colored light." (5) "Irradiation" on page 5, line 4 of the specification is corrected to "projection." (6) "Projection" on page 5, line 11 of the specification is corrected to "projection." (7) "Projection lens" in the first line of page 6 of the specification is corrected to "reflection mirror." (8) In the 7th page, line 12 of the specification, replace ``explained'' with ``
"It is set up," he corrected. (9) “Red, blue, green” on page 7, line 16 of the specification is replaced with “red, blue,
Correct Midori J. (10) "Instructed" on page 8, line 7 of the specification is corrected to "established." (11) Correct Figure 3 as shown in the attached drawing. 7 Appropriate drawings for the list of attached documents (Figure 3) 1
Conversant or above

Claims (1)

[Claims] A transmission type liquid crystal panel is provided between a light source inside the housing of the projection display device and the projection lens, and after the light emitted from the light source is intensity-modulated in the transmission type liquid crystal panel, the light emitted from the light source is transmitted to the outside of the device housing using the projection lens. In a projection display device that projects enlarged images onto a screen installed in A projection type display device characterized by being equipped with means for adjusting from outside the body.