Abstract: A liquid crystal display device has an elliptic polarizer consisting of a polarizer, a first retarder, and a second retarder, and a reflector reflecting light in a visual light range. Optimal values for a twist angle of a liquid crystal layer, an angle between a transmission axis of the polarizer and a slow axis of the first retarder, an angle between the slow axis of the first retarder and a slow axis of the second retarder, and a product of birefringence &Dgr;n of liquid crystal material used in the liquid crystal layer and a thickness d of the liquid crystal layer are evaluated.

Abstract: Light from a light source 10 is linearly polarized by a polarizer 11. Then it propagates via a half-mirror 12 almost parallel to the normal to a reflective liquid-crystal panel 13 and falls on the reflective liquid-crystal panel 13. The reflected light reflected by the reflective liquid-crystal panel 13 is received by a detector 15 via the half-mirror 12 and an analyzer 14. In this state, the reflective liquid-crystal panel 13 is rotated about an axis almost parallel to the normal to the reflective liquid-crystal panel 13 and an angle (extinction angle) at which the output signal of detector 15 reaches minimum is measured. Then, the gap of the reflective liquid-crystal panel 13 is detected based on the measured extinction angle.

Abstract: A liquid crystal display device has an elliptic polarizer consisting of a polarizer, a first retarder, and a second retarder, and a reflector reflecting light in a visual light range. Optimal values for a twist angle of a liquid crystal layer, an angle between a transmission axis of the polarizer and a slow axis of the first retarder, an angle between the slow axis of the first retarder and a slow axis of the second retarder, and a product of birefringence &Dgr;n of liquid crystal material used in the liquid crystal layer and a thickness d of the liquid crystal layer are evaluated.

Abstract: An apparatus for detecting a pretilt angle is comprised of a light source 1, a polarizer 2, a liquid-crystal cell 3, a quarter-wave plate 4, an analyzer 5, a photodetector 6, and a processing device. The processing device receives from the photodetector transmitted light intensities of light that is transmitted through the liquid-crystal cell 3 at a plurality of light incident angles. The processing device calculates Stokes parameters corresponding to the plurality of light incident angles based upon the transmitted light intensity corresponding to the plurality of light incident angles. Furthermore, an apparent retardation corresponding to the plurality of light incident angles is determined based upon the Stokes parameters corresponding to the plurality of light incident angles. The pretilt angle of the liquid-crystal cell 3 is determined based upon the determined apparent retardation corresponding to the plurality of light incident angles.

Abstract: A liquid crystal display device with an In-panel switching system mode includes a conductive body for adjusting an electric field, disposed between elongated electrodes such that the conductive member is electrically isolated from the elongated electrodes.

Abstract: Detachable sunglasses with magnets which are inexpensive, handled easily, not an obstacle when not in use stably attached, and not incongruous when used. Detachable templeless sunglasses comprises templeless sunglasses composed of sunglasses and a frame comprising a magnet to either end thereof, and eyeglasses composed of glasses and a frame comprising a magnet to either end thereof to make said templeless sunglasses detachable to said eyeglasses. The templeless sunglasses are provided with a hinge at the bridge of their frame to make them foldable.