Abstract: The present invention is a composition containing a polyester resin containing at least an alicyclic dicarboxylic acid component and an alicyclic diol component, and it is a polyester resin composition which satisfies that a glass transition temperature is 65° C. or more and 90° C. or less, a refractive index at sodium D line is 1.500 or more and 1.570 or less, a titanium element content is 5 ppm or more and 500 ppm or less, a phosphorus element content is 50 ppm or more and 500 ppm or less and a gel fraction is 50% or less. By the present invention, it is possible to obtain a polyester resin composition having a low refractive index and photoelastic coefficient, and in which a thermally degraded foreign substance is reduced.

Abstract: The present invention provides a polyester composition for a solar battery, which includes a dicarboxylic acid component having terephthalic acid as a main component and a diol component having ethylene glycol as a main component, the polyester composition satisfying the following Formulae (1) to (5): 0.65?intrinsic viscosity?0.90 (1); 0.7?M/P?1.3 (2); 200 ppm?P?600 ppm (3); amount of terminal carboxyl groups?15 eq/t (4); and amount of terminal methoxy groups?10 eq/t (5) (in the Formula (2), M represents the number of moles of an alkaline metal element and/or an alkaline earth metal element per 106 g of a polyester; and P represents the number of elemental phosphorus per 106 g of a polyester).

Abstract: The present invention provides a polyester composition for a solar battery, which includes a dicarboxylic acid component having terephthalic acid as a main component and a diol component having ethylene glycol as a main component, the polyester composition satisfying the following Formulae (1) to (5): 0.65?intrinsic viscosity?0.90 (1); 0.7?M/P?1.3 (2); 200 ppm?P?600 ppm (3); amount of terminal carboxyl groups?15 eq/t (4); and amount of terminal methoxy groups?10 eq/t (5) (in the Formula (2), M represents the number of moles of an alkaline metal element and/or an alkaline earth metal element per 106 g of a polyester; and P represents the number of elemental phosphorus per 106 g of a polyester).

Abstract: The optical pickup device according to the present invention includes: a light source which emits a first light at a first wavelength, a second light at a second wavelength and a third light at a third wavelength; an optical path combining unit which combines vectors of the first, second and third light emitted by the light source, and matches optical axes of the first light and the third light; a light collection unit which condenses the light from the optical path combining unit into the optical information storage medium; a diffraction element which diffracts reflected light from the optical information storage medium; a first photo detector, a second photo detector and a third photo detector which receives the diffracted light from the first diffraction element; and a prevention unit formed between the first diffraction element and the first photo detector, the second photo detector and the third photo detector, and which prevents irradiation of + first-order diffracted light diffracted by the first diffr

Abstract: A polyester composition produced without using an antimony compound as a polycondensation catalyst and including (I) a composition containing, on a weight basis, 30 ppm or less of antimony, 0.5 to 50 ppm of titanium, and 0.1 to 100 ppm of phosphorus, in which the number density of titanium-containing particles, the equivalent circular diameter of which is 1 ?m or more, is less than 100/0.02 mg; and (II) a composition containing, on a weight basis, antimony, titanium and phosphorous as defined above, in which organic polymer particles are contained in amount of 0.1 to 5 wt %, the organic polymer particles having an average particle diameter determined by dynamic light scattering of 0.05 to 3 ?m and containing 0.01% or less of coarse particles relative to the total number of the particles, the coarse particles having a diameter at least twice the average particle diameter.

Abstract: The present invention is a composition containing a polyester resin containing at least an alicyclic dicarboxylic acid component and an alicyclic diol component, and it is a polyester resin composition which satisfies that a glass transition temperature is 65° C. or more and 90° C. or less, a refractive index at sodium D line is 1.500 or more and 1.570 or less, a titanium element content is 5 ppm or more and 500 ppm or less, a phosphorus element content is 50 ppm or more and 500 ppm or less and a gel fraction is 50% or less. By the present invention, it is possible to obtain a polyester resin composition having a low refractive index and photoelastic coefficient, and in which a thermally degraded foreign substance is reduced.

Abstract: A polyester composition produced without using an antimony compound as a polycondensation catalyst and including (I) composition containing, on a weight basis, 30 ppm or less of antimony, 0.5 to 50 ppm of titanium, and 0.1 to 100 ppm of phosphorus, in which the number density of titanium-containing particles, the equivalent circular diameter of which is 1?m or more, is less than 100/0.02 mg; and (II) a composition containing, on a weight basis, antimony, titanium and phosphorous as defined above, in which organic polymer particles are contained in amount of 0.1 to 5 wt%, the organic polymer particles having an average particle diameter determined by dynamic light scattering of 0.05 to 3?m and containing 0.01% or less of coarse particles relative to the total number of the particles, the coarse particles having a diameter at least twice the average particle diameter.

Abstract: A packaging structure suitable for an integrated circuit device receiving short-wavelength laser light is provided. A lead-mounted substrate is placed on the side of the light receiving surface of the integrated circuit device having a photo detecting part. The lead is electrically connected with the integrated circuit device via an electrode. The integrated circuit device and the substrate are encapsulated with an encapsulation section. The substrate has an opening at a position above the photo detecting part.

Abstract: The test circuit according to the present invention includes: a plurality of light-receiving elements; a plurality of amplifiers, each of which converts, into a voltage, a photoelectric current supplied from one of the light-receiving elements; and an electric current supplying unit which supplies an electric current to each of the light-receiving elements and each of the amplifiers.

Abstract: There is provided a light receiving circuit capable of preventing an output variation of the light receiving circuit due to a change in ambient temperature with a simple configuration. The light receiving circuit is provided with a photodiode 4 for LD power monitoring and an I-V amplifier 5 connected with a feedback resistor 13, wherein a light receiving section 16 of the photodiode 4 is covered with a protective film 19. Temperature dependences between a light transmittance of the protective film 19 in accordance-with a shift of a wavelength of a laser beam due to a change in ambient temperature, and a resistance value of the feedback resistor 13 are set in such a way that they may be mutually compensated and an output voltage from the light receiving circuit may be constant for a temperature change.

Abstract: An amplifier circuit according to the present invention includes: a first operational amplifier having a negative input terminal, a positive input terminal, and an output terminal; a photodiode connected to the negative input terminal; a first resistor inserted between the output terminal and the negative input terminal; and a second resistor inserted between the output terminal and the positive input terminal, in which the amplifier circuit outputs current from the output terminal via the second resistor.

Abstract: Disclosed is a light receiving device for reading an optical medium compliant with any of different standards. The receiving device includes light receiving elements and an amplifier circuit. Each light receiving element is for receiving light reflected from an optical medium compliant with a different one of the standards and output a signal responsive to the received light. The amplifier circuit is for amplifying a signal derived from output of the light receiving elements. The signal amplified by the amplifier circuit is derived by subtracting an output signal of one of the light receiving elements that receives light from the optical medium from an output signal of the other light receiving elements.

Abstract: The optical pickup device according to the present invention includes: a light source which emits a first light at a first wavelength, a second light at a second wavelength and a third light at a third wavelength; an optical path combining unit which combines vectors of the first, second and third light emitted by the light source, and matches optical axes of the first light and the third light; a light collection unit which condenses the light from the optical path combining unit into the optical information storage medium; a diffraction element which diffracts reflected light from the optical information storage medium; a first photo detector, a second photo detector and a third photo detector which receives the diffracted light from the first diffraction element; and a prevention unit formed between the first diffraction element and the first photo detector, the second photo detector and the third photo detector, and which prevents irradiation of + first-order diffracted light diffracted by the first diffr

Abstract: The present invention is intended to prevent a light-emitting diode from emitting light continuously in the case when the level at an input terminal is fixed high because of software or the like and to avoid various problems, such as battery exhaustion and breakdown of the light-emitting diode, in PDAs, cellular phones, etc. For these purposes, a high-pass filter 21 for passing the high-frequency components of an optical transmission input signal having a pulse waveform and a binary circuit 22 for binarizing the output signal of the high-pass filter 21 so as to be returned to a pulse waveform are provided in the preceding stage of a light-emitting device driving circuit 23 for driving a light-emitting diode 8 for optical transmission.

Abstract: The test circuit according to the present invention includes: a plurality of light-receiving elements; a plurality of amplifiers, each of which converts, into a voltage, a photoelectric current supplied from one of the light-receiving elements; and an electric current supplying unit which supplies an electric current to each of the light-receiving elements and each of the amplifiers.

Abstract: An amplifier circuit according to the present invention includes: a first operational amplifier having a negative input terminal, a positive input terminal, and an output terminal; a photodiode connected to the negative input terminal; a first resistor inserted between the output terminal and the negative input terminal; and a second resistor inserted between the output terminal and the positive input terminal, in which the amplifier circuit outputs current from the output terminal via the second resistor.

Abstract: A packaging structure suitable for an integrated circuit device receiving short-wavelength laser light is provided. A lead-mounted substrate is placed on the side of the light receiving surface of the integrated circuit device having a photo detecting part. The lead is electrically connected with the integrated circuit device via an electrode. The integrated circuit device and the substrate are encapsulated with an encapsulation section. The substrate has an opening at a position above the photo detecting part.

Abstract: Disclosed is a light receiving device for reading an optical medium compliant with any of different standards. The receiving device includes light receiving elements and an amplifier circuit. Each light receiving element is for receiving light reflected from an optical medium compliant with a different one of the standards and output a signal responsive to the received light. The amplifier circuit is for amplifying a signal derived from output of the light receiving elements. The signal amplified by the amplifier circuit is derived by subtracting an output signal of one of the light receiving elements that receives light from the optical medium from an output signal of the other light receiving elements.

Abstract: There is provided a light receiving circuit capable of preventing an output variation of the light receiving circuit due to a change in ambient temperature with a simple configuration. The light receiving circuit is provided with a photodiode 4 for LD power monitoring and an I-V amplifier 5 connected with a feedback resistor 13, wherein a light receiving section 16 of the photodiode 4 is covered with a protective film 19. Temperature dependences between a light transmittance of the protective film 19 in accordance-with a shift of a wavelength of a laser beam due to a change in ambient temperature, and a resistance value of the feedback resistor 13 are set in such a way that they may be mutually compensated and an output voltage from the light receiving circuit may be constant for a temperature change.

Abstract: The present invention aims to provide a practical polyester that can be produced substantially without using an antimony compound as a polycondensation catalyst. (I) The present invention provides a polyester resin composition containing, on a weight basis, 30 ppm or less of antimony, 0.5 to 50 ppm of titanium, and 0.1 to 100 ppm of phosphorus, in which the number density of titanium-containing particles, the equivalent circular diameter of which is 1 ?m or more, is less than 100/0.02 mg; and (II) The present invention provides a polyester resin composition containing, on a weight basis, 30 ppm or less of antimony, 0.5 to 50 ppm of titanium, and 0.1 to 100 ppm of phosphorus, in which organic polymer particles are contained in amount of 0.1 to 5 wt %, the organic polymer particles having an average particle diameter determined by dynamic light scattering of 0.05 to 3 ?m and containing 0.