Abstract: A display apparatus, that includes current driving type luminescent elements, has a driving system that takes the conduction types of TFTs to control the emission of the luminescent elements into consideration. In order to reduce driving voltage and improve display quality simultaneously, the arrangement is provided such that if the second TFT (30) which performs the “on-off” function of the current for the luminescent element (40) is of an N channel type, the potential of the common power supply line (“com”) is lowered below the potential of the opposite electrode (“op”) of the luminescent element (40) to obtain a higher gate voltage (“Vgcur”).

Abstract: The invention provides a method and apparatus to obtain accurate gradation by obtaining an accurate ratio of light emitting parts in a display device which implements gradation by forming a plurality of TFTs and a plurality of OELDs in each pixel, directly connecting the TFTs and OELDs, and switching an on and off state of the TFTs, and controlling a light emitting area of the OELDs. A plurality of OELDs have the same shape, and gradation can be implemented by controlling the number of OELDs that emit light. A plurality of OELDs have a round shape. A plurality of OELDs are arranged at the same interval in a vertical and/or horizontal direction. According to this structure, because the light emitting areas of the plurality of OELDs become equal to each other, by controlling the number of OELDs, a ratio of the light emitting areas can be accurately obtained.

Abstract: A display apparatus provides a reduction in the off current of a switching thin-film transistor and an increase in the on current of a current thin-film transistor in a current-drive thin-film transistor display apparatus. The switching thin-film transistor is formed as a transistor of LDD structure or offset structure while the current thin-film transistor is formed as a transistor of self-alignment structure. Alternatively, each of the switching thin-film transistor and the current thin-film transistor is formed as a transistor of LDD structure or offset structure, and the LDD length or offset length of the switching thin-film transistor is increased relative to that of the current thin-film transistor.

Abstract: The invention provides a method and apparatus for generating a precise and stable voltage at a high speed. More specifically, there is provided a D/A converter constructed using capacitors having capacitance values which are properly deviated from binary-weighted (2n) capacitance values. This D/A converter has the feature that even if the ratios among a plurality of actual capacitances having weighted values are different from the designed values to an extreme degree, the capacitance value of the jth capacitor is always greater than the sum of the capacitance values of the first through (j-1)th capacitors. This ensures that an unwanted reverse change in the output signal of the D/A converter is prevented from occurring. Furthermore, this technique of the invention can be accomplished without having to use an additional circuit such as a compensation circuit, and therefore this technique is easy and inexpensive.

Abstract: The invention provides a method and apparatus to obtain accurate gradation by obtaining an accurate ratio of light emitting parts in a display device which implements gradation by forming a plurality of TFTs and a plurality of OELDs in each pixel, directly connecting the TFTs and OELDs, and switching an on and off state of the TFTs, and controlling a light emitting area of the OELDs. A plurality of OELDs have the same shape, and gradation can be implemented by controlling the number of OELDs that emit light. A plurality of OELDs have a round shape. A plurality of OELDs are arranged at the same interval in a vertical and/or horizontal direction. According to this structure, because the light emitting areas of the plurality of OELDs become equal to each other, by controlling the number of OELDs, a ratio of the light emitting areas can be accurately obtained.

Abstract: A digital-analog converter, a circuit board, an electronic device, and a liquid crystal display device are provided that make it possible to decrease the number of required resistors and switches and to reduce power consumption. A digital-analog converter that converts plural bits of a digital signal into an analog output, comprises high-potential wiring to which a high potential V.sub.H is supplied, low-potential wiring to which a low potential V.sub.L is supplied, output wiring for obtaining the analog output V.sub.S, a first variable resistance block R1 that is provided between the high-potential wiring and the output wiring and has a variable resistance value, and a second variable resistance block R2 that is provided between the output wiring and the low-potential wiring and has a variable resistance value.

Abstract: A display device including a composite multi-layer film obtained by alternately laminating films and liquid crystal layers a plurality of times is held between one pair of substrates, and a voltage is applied to the composite multi-layer film to control the reflection factor of the composite multi-layer film. In the display device comprising a composite multi-layer film obtained by alternately laminating films and liquid crystal layers, a voltage being applied to the composite multi-layer film to control the reflection factor of the composite multi-layer film, a refractive factor n.sub.LC1(.lambda.n), in a major axis direction, and a refractive factor n.sub.LC2(.lambda.n), in a minor axis direction, of a liquid crystal used in the liquid crystal layers with respect to light having a predetermined wavelength (.lambda.n), and a refractive factor n.sub.F1(.lambda.n) and a refractive factor n.sub.F2(.lambda.

Abstract: The invention provides a method and apparatus for generating a precise and stable voltage at a high speed. More specifically, there is provided a D/A converter constructed using capacitors having capacitance values which are properly deviated from binary-weighted (2n) capacitance values. This D/A converter has the feature that even if the ratios among a plurality of actual capacitances having weighted values are different from the designed values to an extreme degree, the capacitance value of the jth capacitor is always greater than the sum of the capacitance values of the first through (j-1)th capacitors. This ensures that an unwanted reverse change in the output signal of the D/A converter is prevented from occurring. Furthermore, this technique of the invention can be accomplished without having to use an additional circuit such as a compensation circuit, and therefore this technique is easy and inexpensive.

Abstract: A novel phthalocyanine compound having improved solubility and high purity and containing a polymerizable vinyl group within its molecule is provided. Intermediates to this phthalocyanine compound also have improved solubility and high purity. Further, with the novel phthalocyanine compound used as a starting monomer, a novel polymer is obtained which has a high content of (metal) phthalocyanine and is easy to control the orientation of phthalocyanine rings. The polymer having improved solubility and high purity is expected of use as functional material such as catalysts and recording material.

Abstract: Novel naphthalocyanine compounds are provided including nitro- and amino-substituted naphthalocyanine compounds, and vinyl-containing naphthalocyanine compounds. The compounds have improved solubility and high purity and are expected to find use as photo-functional materials such as dyes. Polymers are obtained using the vinyl-containing naphthalocyanine compounds. The polymers also have improved solubility, high purity, a high naphthalocyanine content and ease of control of the orientation of naphthalocyanine rings and are expected of use as various functional materials.

Abstract: Novel naphthalocyanine compounds are provided including nitro- and amino-substituted naphthalocyanine compounds, and vinyl-containing naphthalocyanine compounds. The compounds have improved solubility and high purity and are expected to find use as photo-functional materials such as dyes. Polymers are obtained using the vinyl-containing naphthalocyanine compounds- The polymers also have improved solubility, high purity, a high naphthalocyanine content and ease of control of the orientation of naphthalocyanine rings and are expected of use as various functional materials.

Abstract: A novel phthalocyanine compound having improved solubility and high purity and containing a polymerizable vinyl group within its molecule is provided. Intermediates to this phthalocyanine compound also have improved solubility and high purity. Further, with the novel phthalocyanine compound used as a starting monomer, a novel polymer is obtained which has a high content of (metal) phthalocyanine and is easy to control the orientation of phthalocyanine rings. The polymer having improved solubility and high purity is expected of use as functional material such as catalysts and recording material.

Abstract: A novel phthalocyanine compound having improved solubility and high purity and containing a polymerizable vinyl group within its molecule is provided. Intermediates to this phthalocyanine compound also have improved solubility and high purity. Further, with the novel phthalocyanine compound used as a starting monomer, a novel polymer is obtained which has a high content of (metal) phthalocyanine and is easy to control the orientation of phthalocyanine rings. The polymer having improved solubility and high purity is expected of use as functional material such as catalysts and recording material.

Abstract: In changing or otherwise handling sequential videotex codes composed of geometric codes representing individual image areas as respective geometric drawings and also characteristic codes representing attributes of the geometric drawings, the order of transmission of the geometric codes and characteristic codes is supervised on an order table and a characteristic code table is provided for supervising the characteristic codes, with correction or rearranging of the videotex code data being effected on these tables.

Abstract: A digital phase locked loop (PLL) circuit having an input terminal to which an input digital signal is supplied, a counter for counting a reference clock, a digital phase comparator for comparing the phases of the input digital signal and the output of the counter, a digital low-pass filter supplied with the output of the digital phase comparator, a correction control signal generating circuit and a control circuit, whereby the quantization error is reduced to improve the follow-up characteristic of the digital PLL circuit. Also, the digital PLL circuit contains no residual phase error and this highly-stable digital PLL circuit is arranged so as not to respond to a high frequency fluctuation component such as a peak shift.

Abstract: An image signal encoding system wherein image signal is directly taken in through video camera, changed to digital data, broken down into PDI basic patterns, and then converted into NAPLPS code automatically. The taken-in image signal is divided into a plurality of areas and the information amount of the image signal is reduced for adequate encoding after taking in the image signal. Usually "POLYGON" command is used as the NAPLPS code.