公开(公告)号：JPH07181484A

公开(公告)日：1995-07-21

申请号：JP27663393

申请日：1993-11-05

Applicant: IBM

Inventor： YAMAGUCHI AKIYA ,  KURIHARA MIKIO ,  NISHI SATORU ,  KIMURA YASUHIRO

IPC: G02F1/1335 ,  F21V8/00 ,  F21V19/04 ,  G02B6/00 ,  G02F1/13357

Abstract: PURPOSE: To obtain a back light for liquid crystal display device and a liquid crystal display device where a light source can be safely and easily replaced in perpendicular from the rear side in a small space and the cost is reduced. CONSTITUTION: A lamp guard unit 26 of a back light 20 is freely detachable from a lamp hold unit 24, which is fixed to a light transmission plate 22, in the direction orthogonal to the light irradiated face of the light transmission plate 22. Consequently, it is unnecessary to replace the whole of the back light 20 when a fluorescent lamp 44 is replaced, and a user is safe because he doesn't touch the fluorescent lamp 44 difficult to handle, and further, only a small space is required for detachment ecause it is pulled out in the perpendicular direction, and thus, the fluorescent lamp 44 is safely and easily replaced in the small space.

公开(公告)号：JPH09129382A

公开(公告)日：1997-05-16

申请号：JP26883495

申请日：1995-10-17

Applicant: IBM

Inventor： WATANABE YOSHIAKI ,  YAMAGUCHI AKIYA ,  SUZUKI MASARU

IPC: G02B6/00 ,  G02F1/133 ,  H05B41/24 ,  H05B41/285

Abstract: PROBLEM TO BE SOLVED: To cope with delay in lighting up caused by high pressure cable failure or darkness effect by comparing current values of current detection means of a transformer secondary winding and current detection means of electric discharge tube with each other, and shutting out a power supply when a difference of specified value or more is detected. SOLUTION: A current detected current detection part 31 is installed on the side of secondary winding 21b of a transformer is called I-tr while a detected current of tube current detection part 25 detecting a current flowing in an electric discharge tube 15 is called I-lamp. When the currents I-tr and I-lamp are input to a comparator 33 and it is found that the difference therebetween is over a specified value, it is determined abnormal and a shut out signal is output to a power supply. With the provision of current detection means on the secondary side of transformer, the purpose is attained.