Focus correcting device

Abstract

Abstract PURPOSE:To apparently improve the focus characteristic of a part on a screen, whose focus characteristic deteriorates, by providing a means which emphasizes the high-pass frequency components of a video signal projected on a area on a screen, whose focus characteristic deteriorates, rather than the video signal of other parts. CONSTITUTION:The only prescribed high-pass frequency component 105 of an inputted luminance signal 101 is extracted by a high-pass passing filter 3a, first of all. This frequency band is decided corresponding to the focus characteristic of each display. The gain of the extracted high-pass frequency component 105 is adjusted by a gain adjusting circuit 4a according to the position of the screen, based on a gain adjusting signal 104. The high-pass frequency component 106 whose gain is adjusted is added to a luminance signal 101 by an adder 5a, applied to an inverse matrix circuit 6. Then, R, G and B signals 108, 109, and 110 whose high-pass components are more emphasized as for the surrounding parts of the screen are outputted from the inverse matrix circuit 6. Thus, the picture in which the focus characteristic of the surrounding parts on the display face of a display device is apparently improved, can be projected.

Inventors

• 👤 Tadashi Kasezawa
• 👤 正 加瀬沢

Bibliographic Details