Abstract:
During a period in which electron beam emission to a photo-emissive screen is inhibited, a heating current is supplied to a cathode. During a period in which electron beam emission to the screen is enabled, the supply of the heating current to the cathode is interrupted and the potential at the cathode is varied with a video signal. During the beam emission enabling period, the interruption of the heating current supply allows the electron beam to be uniform along the cathode, since the heating current would cause a potential gradient or variation along the cathode. In addition, during the beam emission enabling period, since the cathode potential is varied with the video signal, the electron beam is modulated in accordance with the video signal.
Abstract:
An electronic apparatus having a plurality of antennas and a plurality of telecommunication modules equipped with a telecommunication function for transmitting and receiving data by simultaneously using a plurality of antennas comprises: an antenna changeover switch for changing the connection of the antennas to the telecommunication modules; and a judgment circuit, which refers to an LED output-use signal output from each of the telecommunication modules used for turning on/off an LED in order to externally display an operation state, determines whether or not an antenna is connected to a telecommunication module in operation and thereby controls the antenna changeover switch.
Abstract:
An image display device has a plurality of electrodes that control a beam between a group of linear cathodes (2) and a screen (8) with a phosphor layer, and is provided with a circuit (31) for generating a beam track offset signal, which generates a signal for slightly oscillating one of the beams horizontally, a PIN photodiode (33) for detecting the emission amount of the phosphor layer for this beam, a comparator (35) for generating a beam irradiation position misalignment signal based on the detected emission amount, an integrating circuit (36) for generating a beam position control signal in correspondence with the beam irradiation position misalignment signal; and a horizontal deflection electrode driving circuit (39) for driving a horizontal deflection electrode (6) in accordance with the beam position control signal. With this configuration, misalignments of the position of the beam spot and the phosphor stripes on the screen, which are caused for various reasons, can be suppressed, and an image display device is obtained, in which a deterioration of the image quality, such as color misalignments, does not occur.
Abstract:
A driving circuit for a capacitive load includes an amplifier for applying voltage with large amplitude to the capacitive load in order to reduce the power consumption of the amplifier is disclosed. The driving circuit for the capacitive load applies the voltages Vout, Vout' amplified by a first amplifier and a second amplifier Q.sub.2, Q.sub.3, Q.sub.2 ', Q.sub.3 ' to a first capacitive load C, and a second capacitive load C'. The applied voltages Vout and Vout' have the opposite phase to each other. The driving circuit for the capacitive load includes a first emitter follower circuit Q.sub.1 and a second emitter follower circuit Q.sub.1 ' for converting the supplied voltage Vcc from the power supply source of the driving circuit to the voltage which is higher by predetermined voltages E.sub.1, E.sub.1 ' than the output voltage Vout, Vout' of the first amplifier and the second amplifier respectively. The driving circuit for the capacitive load includes a switching part using diodes D.sub.1 and D.sub.2 (D.sub.1 ' and D.sub.2 ') for switching automatically to connect the power supply terminal of the first amplifier (second amplifier) with either the output of the emitter follower circuit Q.sub.1 (Q.sub.1 ') or the second capacitive load C (the first capacitive load C').
Abstract:
A communication connection apparatus connected between a facsimile modem apparatus and a facsimile apparatus is provided for connecting the facsimile modem apparatus with the facsimile apparatus through a pair of transmission lines so as to execute communication between the facsimile modem apparatus and the facsimile apparatus. Further, a DC power source applies to a pair of transmission lines through a resistor, a predetermined DC voltage for transmitting an analog facsimile signal transmitted from either one of the facsimile modem apparatus and the facsimile apparatus so as to superimpose the analog facsimile signal on the DC voltage through a pair of transmission lines. In the communication connection apparatus, there is preferably further provided a diode connected between the DC power source and the resistor in a direction of a polarity of the diode such that the predetermined DC voltage is applied to a pair of transmission lines. A facsimile modem apparatus may include the communication connection apparatus.
Abstract:
A wire shaped electron source includes a heating core wire, an insulator partially provided on the heating core wire, and an electron emission material provided on the heating core between the insulators. The thickness of the electron emission material is less than the height of the insulators. When the wire shape electron source is installed in a flat panel display device, the insulator prevents the electron emission material from vibrating thus preventing any contact with the inner wall of the flat panel display device.
Abstract:
Apparatus and method for substantially equalizing the potential drop along a line cathode used in an electron beam source adapted for use in a flat display device. The apparatus and method ensure that electrons from a power source are fed through both ends of the line cathode, substantially simultaneously. Thereby, the potential drop along the axial length of the line cathode is decreased, improving the uniformity of brightness of the display.