1. Field of the Invention
The present invention relates to a front projection type screen, and more particularly, to a front projection type screen which can realize an image quality with high brightness.
2. Description of the Related Art
In general, a projection display can be divided into a front projection type screen and a rear projection type screen. In the front projection type, an image is projected from a projector onto the front projection type screen and displayed thereon. A size of the front projection type screen is much greater than the rear projection type screen. In contrast, the rear projection type screen, which is usually adopted in typical projection televisions exhibits, provides superior image quality compared to the front projection type.
The difference in the image quality between the front projection type screen and the rear projection type screen lies in a difference in structure of each screen. The rear projection type screen uses a dark tint screen providing high contrast and enabling high brightness by decreasing an angle of visibility in a vertical direction and increasing an angle of visibility in a horizontal direction.
A white screen 1, shown in FIG. 1, is typically used as the front projection type screen. As shown in FIG. 1, the white screen 1 reflects incident light in all directions in a substantially uniform manner. Thus, a viewing angle increases while brightness of the screen decreases. FIG. 2 is a graph showing a distribution of light quantity in relation to an angle of visibility of light reflected by the front projection type screen of FIG. 1.
FIG. 3 shows a conventional front projection type screen in which glass beads 7 are distributed on a screen base 5. Referring to the drawing, when the glass beads 7 are used, because incident light is reflected at an angle within a limited range, the brightness of the screen is superior to that of the white screen 1 in FIG. 1. However, because the angle of visibility in the horizontal direction is the same as that in the vertical direction, an efficiency of light is lowered, making it difficult to secure a desired brightness. Also, diffused reflection occurs as disturbance light overlaps the light emitted from a projector (not shown), thus lowering contrast.
As can be seen in the above, in the conventional front projection type screen, when an angle of visibility, that is, a viewing angle, increases, brightness is lowered, and when brightness is increased, the angle of visibility decreases.