JP2715618B2 - Projector device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projector device capable of compensating for dimming of peripheral parts and degradation of resolution.

[Prior Art] For example, a television type projector device A is a third type.
As shown in the figure, the image formed on the fluorescent surface of the projection tube 1 is magnified by the projection lens 2 and reflected by the mirror 3 to make the screen 4
Is formed.

[Problems to be solved by the invention]

However, the projection lens 2 tends to gather the best points of its characteristics on the optical axis due to its inherent physical properties, and therefore, even when projecting an image of the same brightness (for example, a white plate image),
There is a problem of peripheral dimming that the peripheral portion becomes darker than the central portion on the screen 4, and there is also a problem that the resolution in the peripheral portion is deteriorated.

The present invention has been made in view of such a point,
It is an object of the present invention to provide a projector device that compensates for dimming of an image in a peripheral portion and also improves resolution.

[Means for Solving the Problems] For this purpose, the present invention relates to a projector device which enlarges a light image formed by an RGB projection tube with a projection lens and then forms an image on a screen. Is a deformed raster in which the original image is enlarged in the peripheral portion than in the central portion, a concave mirror is provided between the projection lens and the screen, and the concave mirror transforms the deformed raster into a raster shape corresponding to the original image. It was configured to return and reflect off the screen.

〔Example〕

Hereinafter, examples of the present invention will be described. FIG. 1 is an explanatory view of a projector device B of one embodiment, and FIG. 2 is an explanatory view of an operation.

The raster has the same regular shape as the projection screen for the G projection tube originally arranged at the center, but the R and B projection tubes arranged on both sides of the raster have a trapezoidally deformed shape. I have.

In the present embodiment, the original shape is further modified for each of the RGB projection tubes. However, this deformation is such that the image becomes larger from the center toward the periphery. That is, in the enlargement method, the size of the central portion of the image is made the same as the original size, and the enlargement ratio is increased based on a certain rule as the distance from the center increases.

For example, for the G projection tube located in the center, the second
As shown in the figure, a raster 6 whose peripheral portion is enlarged compared to the original raster shape 5 is formed. Then, the deformed raster is corrected to the original raster shape by the optical system between the projection lens 2 and the screen 4, and is projected on the screen 4.

In this embodiment, as shown in FIG. 1, a concave mirror is used as the mirror 7 to reduce the peripheral portion, thereby returning the image to its original shape and size. At this time, since the enlarged portion is reduced, the amount of light in that portion is increased, the luminance is improved, and the resolution is also improved.

Therefore, on the surface of the screen 3, the brightness and the resolution of the peripheral portion can be increased to the same level as the central portion.

In addition, it is desirable that the above-mentioned certain rule for the deformation of the raster be a rule that is easily corrected by the optical system later and returned to the original state. This constant rule may be linear or non-linear, but the enlargement rate must be higher at the periphery of the image than at the center.

〔The invention's effect〕

As described above, according to the present invention, a portion remote from the center of the screen surface is reduced and displayed by the optical system, so that the same amount of light and resolution can be obtained in that portion. Thus, a well-balanced image in which a decrease in peripheral light amount and a deterioration in resolution can be suppressed can be realized.

Further, in the present invention, since the method of deforming the raster shape is adopted, the deformation can be easily realized by the RGB projection tube, and the adjustment of the deformation is easy. Especially,
Since the raster shape can be arbitrarily adjusted so as to correspond to the concave mirror, desired characteristics can be easily obtained. Therefore, even if there is some variation in the concave mirror, it can be absorbed by adjusting the raster shape.

Further, since the concave mirror is provided at the position where the conventional mirror is disposed, the raster shape is restored at the same time as the reflection of the raster, and there is no need to provide a special lens or the like.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a projector device according to an embodiment of the present invention, FIG. 2 is an explanatory diagram of raster deformation, and FIG. 3 is an explanatory diagram of a conventional projector device. 1 ... Projection tube, 2 ... Projection lens, 3 ... Mirror, 4 ...
... Screen, 5 ... Original raster, 6 ... Deformed raster, 7 ... Mirror.

Claims (1)

(57) [Claims] 1. A projector device for enlarging a light image formed by an RGB projection tube with a projection lens and then forming an image on a screen, wherein a raster formed by the RGB projection tube is positioned such that an original image is located closer to the periphery than to a central portion. A deformed raster enlarged by the portion, a concave mirror is provided between the projection lens and the screen, and the concave mirror is configured to return the deformed raster to a raster shape corresponding to the original image and to reflect the deformed raster to the screen. A projector device characterized by the above-mentioned.