Backlight with integrated Piezo Ceramic Speaker.
Publication Date: 2002-May-13
The IP.com Prior Art Database
Backlight with integrated Piezo Ceramic Speaker
A LCD display with integrated (loud)speaker is concept is based on the use of piezo ceramic material that serves as actuator for generating vibrations. When a voltage is applied to piezo ceramic material it tends to bend. This bending can be used for generating vibrations. The piezo ceramic is glued to the back of a LCD display. This causes the piezo ceramics to transmit its vibrations to the display. Because of the construction and larger mass the display then amplifies the initiated vibrations.
For most applications display technology is rapidly changing towards transflective technology. Transflective displays use a backlighting system for illumination. This backlight is located behind the display and radiates light through the display towards the viewer. One of the key items of a good backlight is its ability to create a uniform field of light across the whole surface. In the traditional system the piezo ceramic material is fixated to the back of the display in order to conduct its vibrations to the larger panel. For transflective displays with backlighting this would mean that no longer the area directly behind the display could be used without creating visual artifacts in the display image. the piezo ceramic material can be positioned at different places in order to create a good display speaker system with transflective displays using a backlight.
The piezo ceramic speaker is attached to the backlight. The backlight mostly consists of the following components: light source, lightguide, reflector sheet, optical foils and a housing. Within this concept various construc...