JP2001069434A - Distortion corrector for liquid crystal projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correct a display distortion and to enable accurate display by inputting X and Y coordinates to display prescribed video in a prescribed bearing, reading out the contents of a memory in which coordinate values to be corrected corresponding to these coordinates are previously stored, converting a scanning position and correcting the video projected on a display screen. SOLUTION: A scanning position generating circuit 1 is composed of a counter for counting a clock with one pixel as a minimum unit and generates lateral and longitudinal pixel positions X1 and Y1 synchronously with the synchronizing signal of video. A scanning position converting memory 2 outputs pixel positions X2 and Y2 corresponding to the input pixel positions X1 and Y1. The memory 2 previously stores conversion data for correction. Concerning the correction data, a value is set so as to output the input X1 and Y1 as they are as initial data first of all and the point of a known watching bearing is displayed through a liquid crystal panel 3 for projection onto a display screen 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a distortion correction device for accurately projecting an image on a screen by a liquid crystal projector or the like.

[0002]

2. Description of the Related Art Conventionally, no projection type display system using a liquid crystal projector has distortion correction.

[0003]

Since the conventional liquid crystal projector did not have a distortion correction function, it could not be applied to a high-precision wide-view display device such as a flight simulator using a curved screen and a concave mirror. The purpose is to be able to do this.

[0004]

According to the present invention, in order to achieve the above object, a value for correcting a scanning position is stored in advance in a memory, and a value corresponding to the scanning position when actually scanning is stored. By reading the correction value from the memory,
It is designed to display an image without distortion.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.

1 is a scanning position generating circuit, 2 is a scanning position conversion memory, 3 is a projection liquid crystal plate, and 4 is a display screen. The operation will be described below.

The one scanning position generating circuit is usually constituted by a counter which counts a clock having one pixel as a minimum unit, and synchronizes with a video synchronizing signal in a horizontal pixel position X1 and a vertical pixel position. This is a circuit for generating Y1. 2 scan position conversion memory stores the input pixel position (X
(1, Y1) is a memory that outputs (X2, Y2). This memory stores conversion data for correction in advance. As the correction data, first, as initial data, values such that the input X1 and Y1 are output as they are are set.
Is displayed on the display screen 4 through the projection liquid crystal panel. On the other hand, a point to be projected and displayed on the display screen 4 is used as a reference by, for example, a slide projector or temporarily attaching a marking. FIG. 2 shows an example of a reference point and a display point before correction. For example, the display point A in FIG.
Is corrected to the reference point B, the contents of the memory having the address of the coordinate value of the point A of the scanning position conversion memory 2 (the initial value is the coordinate value of the point A) are corrected to the point B. By rewriting the coordinate values. By performing this for the memories in the entire display area, the entire screen can be corrected. The correction may be performed at predetermined intervals, and interpolation may be performed by interpolation or extrapolation between the intervals.

[0008]

As described above, the display distortion can be easily corrected by adding a memory for correction to the liquid crystal projector which has not been able to correct the distortion of the displayed image, so that the display with high accuracy can be achieved. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a display pattern diagram for explaining creation of distortion correction data according to the present invention.

[Explanation of symbols]

1: Scanning position generating circuit, 2: Scanning position conversion memory, 3:
Liquid crystal panel for projection, 4: display screen.

Claims (1)

[Claims] 1. A liquid crystal projector for scanning a display position and projecting and displaying an image on a display screen by sequentially changing a coordinate value of X and a coordinate value of Y so that a predetermined image is displayed in a predetermined direction. As described above, the apparatus has a memory in which the X coordinate and the Y coordinate are input and the coordinate value to be corrected corresponding to the input is stored in advance. A liquid crystal projector projection distortion correction device that corrects projected images.