Abstract: In a sound multiplex broadcast system employing sound multiple signals having a plurality of sound multiplex modes and a display control method therefor, there are detected kinds of sound multiplex mode of sound multiple signals received by the receiver, a sound multiplex mode is set, a demodulated sound output signal of a mode determined according to the mode detection signals and the mode setting signal is selected from demodulated sound output signals attained by demodulating the received sound multiple signals so as to be supplied to a sound output unit, and a kind of sound multiplex mode of the demodulated sound output signal thus selected is displayed on a display unit.

Abstract: A method and apparatus for forming a fog screen for use in the projection for display of an optical image which comprises disposing a pair of substantially parallel air curtains and blowing a fog into the space defined by and between the air curtains. The fog screen is high and uniform in density and can be utilized for forming a well-defined image thereon that is free from distortions or interruptions.

Abstract: A remote control apparatus has a plurality of manipulating buttons fitted in a plurality of windows, respectively, formed in a casing member, each of the manipulating buttons being formed of a transparent material and having a lower portion provided with a switch actuating projection and an upper portion disposed within each of the windows for allowing user to operate the button with his or her finger. A switch array includes a plurality of switches corresponding to the plural manipulating buttons and is mounted within the casing member such that each of the switches can be changed over between ON and OFF states by contact with a switch actuating projection in the operation of the corresponding manipulating button.