Nokia Display Products Oy

Kimmo Siitari

Pertti Vihtori Saarinen

Juha Nurmi

Use of an especially small-sized and valuable display device (b 31) is limited to persons knowing a password, not by any requirement that a password ( ) always be entered when the display device ( ) is switched on, but rather detecting, the detachment of the display device ( ) from the equipment ( ) controlling it and measuring its time of being detached, for limiting the use of the display device ( ) on the basis of a certain predetermined and adjustable time limit which, when exceeded, requires the password be entered.

Method and arrangement for limiting the use of a display device

The invention relates to a method for adjusting the colour temperature in a liquid crystal display with background lighting. According to the invention, the liquid crystal display is lit by two or more background light lamps with different colour temperatures (LAMP,), the colour temperature range of the background light is extended and better opportunities for adjusting the colour temperature by changing the pass rate of the light are provided. In a more advanced solution, background light lamps with different colour temperatures (LAMP,) are switched on (S,) separately for setting the colour temperature of the display, and furthermore, the brightness of the background light lamps (LAMP,) with different colour temperatures can be adjusted separately for setting the colour temperature.

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Salo, Finland

Kimmo Siitari