Abstract: A full-bridge power converter is provided. A control unit 30 generates control signals for individual switching elements for controlling ON/OFF operation of switching elements 11˜14, alternately turns the switching element 11 and switching element 12 ON/OFF, also alternately turns the switching element 13 and switching element 14 ON/OFF, outputs supply current from a full-bridge circuit 10 for supplying to a load 3, and, during a period when the supply current is not supplied, turns ON both the switching element 11 and switching element 13 to pass inertial current by discharging energy stored in inductors 16 and 17, and filter capacitors 19 and 20 absorb the charge of common-mode noise components appearing on an output line connecting the inductor 16 and an output capacitor 18 and on an output line connecting the inductor 17 and the output capacitor 18.

Abstract: A full-bridge power converter is provided. A control unit 30 generates control signals for individual switching elements for controlling ON/OFF operation of switching elements 11˜14, alternately turns the switching element 11 and switching element 12 ON/OFF, also alternately turns the switching element 13 and switching element 14 ON/OFF, outputs supply current from a full-bridge circuit 10 for supplying to a load 3, and, during a period when the supply current is not supplied, turns ON both the switching element 11 and switching element 13 to pass inertial current by discharging energy stored in inductors 16 and 17, and filter capacitors 19 and 20 absorb the charge of common-mode noise components appearing on an output line connecting the inductor 16 and an output capacitor 18 and on an output line connecting the inductor 17 and the output capacitor 18.

Abstract: A full-bridge power converter is provided wherein a full-bridge circuit is operated so as to minimize ripple current. A switch control unit 20 generates control signals for individual switching elements to control the ON/OFF operation of switching elements of a full-bridge circuit 10, thereby turning a switching element (Q1) 11 and a switching element (Q2) 12 ON and OFF alternately and turning a switching element (Q3) 13 and a switching element (Q4) 14 ON and OFF alternately to output from the full-bridge circuit 10 supply current for supplying to a load 21, and turning ON both the switching element (Q1) 11 and the switching element (Q3) 13 during a period when the supply current is not output, thereby connecting and passing inertial current between the connection points of the full-bridge circuit 10.

Abstract: In a projection type display apparatus including a blue CRT display apparatus with low luminous efficiency and low luminous efficiency, the present invention seeks to improve contrast while suppressing the fall in brightness for red, green, and blue color as a whole. In the projection type display apparatus, the images of three colors outputted from three monochrome CRT display apparatuses 10R, 10G, 10B which respectively output monochromatic video signals of red, green, and blue color, are respectively projected on a screen unit 14 via a reflecting mirror 12 so as to synthesize a image of three colors and generate a color image. The brightness of the green CRT display apparatus which outputs the green image having the highest luminous efficiency is increased, while maintaining the brightness of the blue CRT display apparatus 10B. Further, a light absorption means for tinting to reduce the increased green brightness is provided to balance the whole brightness of red, green, and blue.

Abstract: In a projection type display apparatus including a blue CRT display apparatus with low luminous efficiency and low luminous efficiency, the present invention seeks to improve contrast while suppressing the fall in brightness for red, green, and blue color as a whole. In the projection type display apparatus, the images of three colors outputted from three monochrome CRT display apparatuses 10R, 10G, 10B which respectively output monochromatic video signals of red, green, and blue color, are respectively projected on a screen unit 14 via a reflecting mirror 12 so as to synthesize a image of three colors and generate a color image. The brightness of the green CRT display apparatus which outputs the green image having the highest luminous efficiency is increased, while maintaining the brightness of the blue CRT display apparatus 10B. Further, a light absorption means for tinting to reduce the increased green brightness is provided to balance the whole brightness of red, green, and blue.

Abstract: The cathode-ray tube according to the present invention has on the inner surface of the funnel section of the body thereof a laminated layer comprising a first layer of black material, a metal backing layer and a second layer of black material. According to the configuration of the cathode-ray tube of the present invention, stray light reflected within the body of the cathode-ray tube is absorbed by the first layer of black material on the inner surface of the funnel, while stray light reflected off the inner surface of the funnel is absorbed by the second layer of black material. This makes it possible to reduce the amount of stray light incident upon the effective screen area of the panel section.

Abstract: The cathode-ray tube according to the present invention has on the inner surface of the funnel section of the body thereof a laminated layer comprising a first layer of black material, a metal backing layer and a second layer of black material.

Abstract: A portable HDTV testing device inserts a deterministic test signal having a frequency close to the symbol rate of the received HDTV signal. As the received HDTV signal is randomized prior to broadcast for synchronization purposes, the addition of the deterministic test signal to the randomized data signal is essentially equivalent to the addition of a random (or white) noise signal to an information bearing signal. The use of a deterministic test signal avoids the expense associated with a random signal generator, thus making possible an inexpensive and portable HDTV test device. To test the noise margin of a received signal, which is used to determine if the installation of the antenna and HDTV receiver is optimized, the test unit inserts known levels of the noise signal incrementally and measures the bit error rate until the bit error rate exceeds a known threshold above which proper decoding is not possible.

Abstract: In a thyristor ignition circuit, a forward voltage drop occurring in a signal path of an anode and a gate of a thyristor is reduced. An anode of a thyristor of the thyristor ignition circuit is connected to one signal terminal, and a gate thereof is connected to another signal terminal. The thyristor ignition circuit further comprises a transformer having a primary winding for receiving an ignition signal, and a first secondary winding having one end connected to a cathode of the thyristor and the other end connected to the other signal terminal. The thyristor is ignited via the cathode in response to the ignition signal applied to the transformer. A signal path is established between one signal terminal and the other signal terminal through the anode-to-gate path.

Abstract: A coil (11) is connected in series to a primary winding (1a) of a flyback transformer (1). A series circuit of a capacitor (15) and a switching circuit (12) is connected in parallel to the coil (11). By turning on and off the switching circuit (12), the connection of the capacitor (15) to the coil (11) is switched, to thereby connect or disconnect the coil (11) in an AC fashion. Therefore, it is possible to realize a high voltage regulating circuit which can be made inexpensive.

Abstract: A vertical deflection distortion correction circuit, wherein there are provided a vertical deflection output circuit, a damping circuit, a vertical deflection yoke and a resonance circuit. A current is resonated in the resonance circuit, and on the other hand, a vertical deflection current is derived from the vertical deflection output circuit and supplied to the vertical deflection yoke. Then, the resonated current is superimposed on the vertical deflection current. The superimposed vertical deflection current is finally supplied to the vertical deflection yoke. The resonance circuit is constructed of an LC parallel circuit and a switching element circuit. The switching element circuit is compose of either FETs, or thyristors.

Abstract: A sine wave deflecting circuit has a simplified configuration capable of ensuring an efficient and stable operation with a function of facilitating external synchronization. The deflecting circuit comprises a resonant circuit comprising a deflecting coil and a resonant capacitor, and a circuit for detecting a signal waveform of the resonant circuit and driving the resonant circuit in accordance with the detection signal, wherein the deflecting coil is driven with sine waves generated by self-oscillation. A deflection interruption time is set during the driving action, and the sine-wave driving frequency is controlled by controlling the length of such interruption time.

Abstract: A high voltage generator using a flyback transformer to generate high voltage pulses and including a control switching transistor inserted in a power supply circuit in a manner to be turned off during a trace interval. The amount of electric energy accumulated in a resonance circuit is intermittently controlled by the on-off action of such switching transistor, so that the level of the high pulse voltage outputted via the transformer can be maintained constant to consequently enhance the response characteristic in the voltage regulation while minimizing the number of required component elements.

Abstract: In a horizontal deflection output circuit adapted for correction of horizontal linearity in a television receiver or the like, and which comprises a switching transistor, a damper diode, a horizontal deflecting coil and an S correcting capacitor connected in series to the horizontal deflecting coil; the terminal voltage of the S correcting capacitor is modulated by a sawtooth signal produced by a linear distortion correcting circuit synchronously with a horizontal periodic signal. The sawtooth signal produced by the switching transistor and fed to the horizontal deflecting coil is applied to the S correcting capacitor which feeds an S correcting current to the horizontal deflecting coil, so as to correct the image distortion caused particularly by the resistance component of the horizontal deflecting coil.

Abstract: A television receiver for receiving standard television channel signals and a scrambled television channel signal includes a channel selector which selects one of the television channel signals, a tuner which tunes the selected television channel signal, and a converting circuit which converts the scrambled television channel signal to a vacant standard television channel signal for tuning by the tuner.