CURRENT-CONTROLLED LIGHT-EMITTING DEVICE

• Main Authors: YAMASHITA MASAAKI, MORI HIDEAKI
• Format: Patent
• Language: English
• Published: 02.11.2001
• Edition: 7
• Subjects: ADVERTISING; ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICESUSING STATIC MEANS TO PRESENT VARIABLE INFORMATION; CRYPTOGRAPHY; DISPLAY; EDUCATION; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; PHYSICS; PICTORIAL COMMUNICATION, e.g. TELEVISION; SEALS

PROBLEM TO BE SOLVED: To provide a current-controlled light-emitting device, capable of suppressing variation in luminance in pixels by shortening the switching delay time of a constant current source and realizing luminance control, making a light-emitting element emit light at high speed with a prescribed luminance. SOLUTION: A prescribed current is always conducted into a light-emitting element side, by shortening the switching delay time between the light-emitting element side and a constant voltage source side 46 by providing a switching part 45 at the output terminal (e) point of a constant current source transistor 43 and by changing over the light emitting element side and the constant voltage source side 46, so that the constant current source transistor 43 always turns into a conductive state. Moreover, light emission luminance of pixels can be made uniform, by suppressing the variation of current values due to the variation of the thresholds of constant current source transistors 43 which decides the light emission luminance, while building up circuits of dashed line parts being portions for pixels placed in a horizontal direction in a single integrated circuit.