Matsushita Electric Industrial Co., Ltd. has developed a transparent panel speaker called “Sound Window,” an industry-first speaker that reproduces sound by pneumatically vibrating a transparent panel using aerodynamic-drive technology. Featuring extremely low power consumption and design flexibility that makes it possible to mount the panel speaker onto a display screen or touch panel, “Sound Window” can be applied to a wide variety of small products such as mobile phones and personal digital assistants.
The transparent speaker works by using a transparent panel as the diaphragm, and the driver which generates air pressure can be positioned near the panel. This feature enables the speaker to be mounted over the display screen without interfering with the picture quality. A touch panel configuration also works perfectly as a diaphragm of this aerodynamic-drive speaker technology. Compared with other transparent panel speakers using direct-driven panel, the ‘Sound Window’ speaker system with the aerodynamic-drive technology consumes only 1/25 of power, making its strong advantage in applications to mobile electronic products, such as cell phones and PDA’s.
Conventional speakers in video equipment such as televisions are usually mounted on the front or the rear section of the appliance. A drawback in such configuration is that front-mounted speakers restrict the screen size because in conventional electrodynamic speakers the diaphragm and magnetic circuit are in one body, requiring extra space if it is to be mounted on equipment having a display screen. Also, rear-mounted speakers reproduce sounds with less clarity. The “Sound Window” transparent speaker attempts to eliminate this problem by allowing wide flexibility in choosing the mounting position and designing the shape.
Some of the new technologies being used in the new transparent speaker are the following:
(1) The “aerodynamic drive technology” acoustically vibrates a transparent panel using the sound pressure generated by a driver installed in the space behind the panel. This technology ensures sound-pressure transmission to the entire panel surface, resulting in great flexibility in choosing the installation position of the driver and designing the panel shape.
(2) For driving a large-area panel using a small driver the “acoustic leverage technology” enables a small driver to acoustically vibrate a panel with ten or more times the diaphragm area of the driver. The acoustic leverage works in proportion to the area ratio of speaker panel and driver diaphragm, so that a small driver can efficiently vibrate a large-area panel.
The company plans to mass produce the products at Matsushita Electronic Components Co., Ltd, and ship them to its industrial customers by the end of year.