Abstract: With regard to a display device having an SRAM incorporated in a pixel, a technology is disclosed, which is capable of reducing manufacturing costs by simplifying a constitution of a driver. A write voltage equivalent to white or black represented by a tone level of a normal display area is converted into a write voltage corresponding to a brightest white display or a darkest black display in the pixel, and is held in the SRAM of each pixel. In the case of normal display, display is carried out with the write voltage represented by the tone level of the normal display area. In the case of static image display, display is carried out with the write voltage corresponding to the brightest white display or the darkest black display in the pixel, the write voltage being held in the SRAM. Since the normal display and the static image display can be carried out with a write voltage supplied from one driver, the constitution of the driver can be simplified.

Abstract: An IC socket for testing a grid array package, is configured to be fitted with an adapter socket mounted on a test board. The IC socket includes an IC socket body having a bottom plate formed with a number of contact holding holes penetrating through the bottom plate and arranged in the form of a matrix, and a number of contacts each having a contacting end, a spring portion, a fixing base portion and a contacting pin which are arranged in the named order, the fixing base portion of each of the contacts being inserted into a corresponding contact holding hole of the IC socket body from the upperside of the bottom plate.

Abstract: A magnetic lock device includes a first element and a second element that are capable of being detachably coupled together by attracting each other magnetically under the magnetic interaction of permanent magnets, wherein each of the first and second elements includes an annular permanent magnet having a center bore through it, a ferromagnetic disk-like plate disposed to make contact with the permanent magnet, and a ferromagnetic projecting member extending from the disk-like plate and through the center bore of the permanent magnet. All of the component parts for the first and second elements are covered with any suitable synthetic resin film, sheet or the like and shielded from the outside, so that any foreign matter such as dust, particularly ferromagnetic particles like iron, cannot enter the gap or space that is present between the outer peripheral wall of the projecting member and the inner peripheral wall of the center bore through the annular permanent magnet.