Title:
DISPLAY DEVICE
Document Type and Number:
Japanese Patent JP3231216
Kind Code:
B2
Abstract:
PURPOSE: To expand the variable range of horizontal size of a screen so that videos with aspect ratios of 16:9 and 4:3 are stably switched.
CONSTITUTION: A horizontal sawtooth voltage VSAW is level-compared with an error output voltage VVP from an error amplifier circuit 15 by a comparator 16, and a rectangular comparison output voltage VCO is obtained. A transistor 19 is switch-operated by the comparison output voltage VCO, thereby a horizontal size control current IO is controlled via a choke coil 21, and a horizontal deflecting current IDY in a horizontal deflection output circuit 65 is controlled. Also, the comparison output voltage VCO is inverted and integrated by an inversion circuit 24 and an integration circuit 23 in a flyback voltage formation circuit 80, and a flyback voltage VFB is generated. The flyback voltage VFB is supplied to the error amplifier circuit 15 with a horizontal size reference voltage Vref which decides the horizontal size of the screen, and the level of the error output voltage VVP is controlled so as to keep those levels constant relation.
Inventors:
Makoto Onozawa
Application Number:
JP10968995A
Publication Date:
November 19, 2001
Filing Date:
May 08, 1995
Export Citation:
Assignee:
株式会社日立製作所
International Classes:
H04N7/015; H04N3/223; H04N3/27; (IPC1-7): H04N3/223; H04N3/27
Domestic Patent References:
| JP274987A | ||||
| JP6046171A | ||||
| JP57185261U |
Attorney, Agent or Firm:
Kiyoshi Maruyama (7 outside)