Abstract: The display device (1) which displays a video on a display section (7) includes a video processing circuit (2) and a backlight control circuit (3) for aperiodically changing at least any of a brightness and a contrast of the video, which is displayed on the display section (7), within a predetermined range during a predetermined time period.

Abstract: An apparatus for making a quartz glass crucible comprises a housing having a first chamber and a second chamber therein, a rotation crucible having an inner surface corresponding in configuration to the quartz glass crucible, means for rotating the rotation crucible, means for shifting the rotation crucible and the rotating means together between the first and second chambers, means placed in the first chamber for feeding a grain material into the rotation crucible, means placed in the first chamber for shaping the grain material in the rotation crucible so as to form a shaped body in the shape of the quartz glass crucible when the rotation crucible rotates, and means placed in the second chamber for heating and fusing the shaped body within the rotation crucible so as to make the quartz glass crucible.