Title:
ランプを明るさに依存して制御するための回路装置
Document Type and Number:
Japanese Patent JPH117
Kind Code:
U
Abstract:
In order to provide brightness-dependent control of a lamp which is used for illuminating a LCD display, it is known to switch the lamp on and off in dependence on the measured brightness of the incident ambient light. To prevent overheating of the liquid crystal display when it is, for example, exposed to direct sunlight, the operating voltage for the lamp is changed in dependence on the measured brightness of the incident ambient light. A further improvement is accomplished when, additionally, in dependence on the ambient temperature measured, the operating voltage for the lamp changes, more specifically the operating voltage is switched off when a presettable threshold value is exceeded. The circuit arrangement for performing the method requires very little design effort and cost and is integrable to a very large degree.
Inventors:
Eckardt ヴアルタース
Route ヴイツヒ A デナー line
Route ヴイツヒ A デナー line
Application Number:
JP300098U
Publication Date:
January 12, 1999
Filing Date:
May 06, 1998
Export Citation:
Assignee:
コーニン Klecka Philips Electronics N ヴィ
International Classes:
G09G3/04; G09G3/08; G09G3/18; G09G3/20; G02F1/133; H05B37/02; H05B39/04; (IPC1-7): G02F1/133; H05B37/02
Attorney, Agent or Firm:
Toshio Yano (besides two persons)