Abstract: An optical sensor includes: first and second light receiving elements on a semiconductor substrate; a light blocking film over the semiconductor substrate via a light transmitting film; and first and second openings corresponding to the light receiving elements and disposed in the light blocking film. First and second virtual lines are defined to extend from the centers of the first and second light receiving elements and pass through the centers of the first and second openings, respectively. At least one of elevation angles and left-right angles of the first and second virtual lines are different. The photosensitive area of the first light receiving element is larger than the aperture area of the first opening. The photosensitive area of the second light receiving element is larger than the aperture area of the second opening.

Abstract: An optical sensor includes: first and second light receiving elements on a semiconductor substrate; a light blocking film over the semiconductor substrate via a light transmitting film; and first and second openings corresponding to the light receiving elements and disposed in the light blocking film. First and second virtual lines are defined to extend from the centers of the first and second light receiving elements and pass through the centers of the first and second openings, respectively. At least one of elevation angles and left-right angles of the first and second virtual lines are different. The photosensitive area of the first light receiving element is larger than the aperture area of the first opening. The photosensitive area of the second light receiving element is larger than the aperture area of the second opening.

Abstract: An ultrasonic sensor composed of a substrate and a piezoelectric vibrator mounted on the substrate is advantageously used as a sensor for detecting a distance to an object located in front of an automotive vehicle. Ultrasonic waves transmitted from the sensor are reflected by the object, and the reflected waves are received by the sensor. Based on the reflected waves, the distance from the vehicle to the object is calculated. To reduce rigidity and thereby to lower a resonant frequency of the substrate to a desirable level, grooves are formed in the substrate. A thickness of the substrate is not reduced to maintain its mechanical strength against an impact force. A resonant frequency which is desirable to realize a sufficiently high directivity and sensitivity is obtained in this manner without enlarging a size of the ultrasonic sensor.

Abstract: An ultrasonic sensor composed of a substrate and a piezoelectric vibrator mounted on the substrate is advantageously used as a sensor for detecting a distance to an object located in front of an automotive vehicle. Ultrasonic waves transmitted from the sensor are reflected by the object, and the reflected waves are received by the sensor. Based on the reflected waves, the distance from the vehicle to the object is calculated. To reduce rigidity and thereby to lower a resonant frequency of the substrate to a desirable level, grooves are formed in the substrate. A thickness of the substrate is not reduced to maintain its mechanical strength against an impact force. A resonant frequency which is desirable to realize a sufficiently high directivity and sensitivity is obtained in this manner without enlarging a size of the ultrasonic sensor.

Abstract: A fluorescent display tube including a substrate, a plurality of anodes formed on the substrate, fluorescent layers formed on the respective anodes, cathodes located above the fluorescent layers to generate electrons which strike the fluorescent layers, ribs formed of an electrically insulating material on the substrate so as to surround at least a portion of a periphery of each of the anodes and having a larger height from the substrate than the fluorescent layers, and grid electrodes formed on the respective ribs to control activation of the fluorescent layers. Each rib consists of a plurality of layers laminated by screen printing using a paste which includes the electrically insulating material.

Abstract: A fluorescent display tube including a substrate, a plurality of anodes formed on the substrate, fluorescent layers formed on the respective anodes, cathodes located above the fluorescent layers to generate electrons which strike the fluorescent layers, ribs formed of an electrically insulating material on the substrate so as to surround at least a portion of a periphery of each of the anodes and having a larger height from the substrate than the fluorescent layers, and grid electrodes formed on the respective ribs to control activation of the fluorescent layers. Each rib consists of a plurality of layers laminated by screen printing using a paste which includes the electrically insulating material.

Abstract: A process for separating porphyrins, which comprises(1) adjusting the pH of the liquid phase of a culture broth containing at least two porphyrins to about 2.5 to about 4 and collecting the resulting solid containing the porphyrins,(2) either (a) preparing an acidic aqueous solution of said solid and adjusting the pH of its liquid phase left after removal of insoluble matter to about 6 to about 8 to form an aqueous solution containing the porphyrins, or (b) preparing an acid-containing lower alcohol solution of said solid, adjusting the pH of its liquid phase left after removal of insoluble matter, adding water in an amount at least twice the amount of the solution to precipitate lower alkyl esters of the porphyrins, collecting the precipitates and dissolving them in an organic solvent to form an organic solvent solution of the porphyrin esters,(3) contacting the solution obtained in (a) or (b) in step (2) with a copolymer having a surface area of at least about 700 m.sup.

Abstract: A process for separating vitamin B.sub.12 in pure form, which comprises bringing a vitamin B.sub.12 -containing liquid containing impurities into contact with a resin selected from the group consisting of (A) a divinylbenzene/styrene copolymer having a mode pore diameter of at least about 200 A and a total pore volume of more than 0.6 ml/g, and (B) a copolymer of divinylbenzene/styrene/an unsaturated alkyl ester of an aromatic polycarboxylic acid represented by the formula ##STR1## wherein R represents a C.sub.3 -C.sub.10 unsaturated alkyl moiety having a carbon-carbon double bond and n is 2 or 3, said copolymer (B) having a surface area of at least about 700 m.sup.2 /g, to cause vitamin B.sub.12 to be adsorbed to said resin, and eluting the vitamin B.sub.12 with an eluent, and collecting the active eluate.