Abstract: An illuminance sensor is formed as a current output type sensor that outputs a current which increases or decreases in an analog manner corresponding to an increasing or decreasing change of the illuminance. A light-emitting device is connected with a detection resistor that detects a current flowing through a light-emitting device. A driving control circuit has a light-emitting device driver that outputs to the light-emitting device a voltage for holding a voltage, which is obtained when a current flowing through the light-emitting device and a current detected by the illuminance sensor flows through the detection resistor, in a predetermined value all the time. The light-emitting device emits a large amount of light in a dark place and emits a small amount of light in a bright place.

Abstract: An illuminance sensor is formed as a current output type sensor that outputs a current which increases or decreases in an analog manner corresponding to an increasing or decreasing change of the illuminance. A light-emitting device is connected with a detection resistor that detects a current flowing through a light-emitting device. A driving control circuit has a light-emitting device driver that outputs to the light-emitting device a voltage for holding a voltage, which is obtained when a current flowing through the light-emitting device and a current detected by the illuminance sensor flows through the detection resistor, in a predetermined value all the time. The light-emitting device emits a large amount of light in a dark place and emits a small amount of light in a bright place.

Abstract: A light beam emitted by a surface illuminant reaches the surface of a transparent base layer of a recess/projection detection optical element. A light beam emitted almost vertically is emitted to an air layer. A light beam incident on the transparent base layer at an angle larger than a total reflection angle returns to a two-dimensional photosensor at a portion contacting the air layer, but scatters in a transparent particle at a portion contacting the transparent particle. When a finger is brought into contact with a scattering reflection layer, the scattering reflection state does not change in an area corresponding to a valley of a fingertip. As indicated by an arrow, an amount of reflected light beam is large. In an area corresponding to a ridge of the fingertip, the light beam scattered by the transparent particle is absorbed. The amount of reflected light beam is small, as indicated by an arrow.

Abstract: An illumination panel comprises a light source, a photoconductor for guiding light from the light source, and an optical film for emitting light emitted from the photoconductor ahead of an observer. The photoconductor comprises a stepwise face having an incident end face onto which the light from the light source is projected, step faces, and step differentiating faces for emitting the light guided from the light source and connecting the step faces, and reflective films formed on the step faces. The optical film is arranged at the front side of the photoconductor, and has projected incident portions which are opposite to the step differentiating faces in a light emitting direction. The optical film emits the light emitted from the step differentiating faces ahead, and causes the light that is projected from the front to be reflected ahead on reflective faces on the step faces.

Abstract: A high-speed bevel gear transmission system for transmitting power from an input shaft to a pair of parallel outputs shafts the axes of which intersect each other. The input shaft has a pair of driving bevel gears which are fixedly mounted thereon such that the driving bevel gears face in opposite directions and which have the same number and size of teeth spirally arranged in the opposite directions each other. The output shafts are supported on angular contact ball bearings and have two driven bevel gears fixedly mounted thereon which are engaged with the driving bevel gears. The speed transmission ratio of the output shafts to the input shaft is 1.45:1 to 0.476:0.1, the relation between a pressure angle .alpha. and helix angle .beta. of the driving bevel gears and driven bevel gears, and a pitch cone angle .delta. of the driven bevel gears are defined by the formula, R=[(tan.alpha..multidot.sin .delta.)/cos .beta.]-tan.beta..multidot. cos .delta. when 0.324.ltoreq.R.ltoreq.0.1.

Abstract: A planetary gear type transmission designed to equalize the load on a plurality of planet gears meshed with a sun gear. The planetary gear type transmission includes an intermediate ring or annulus which is disposed between an outer ring gear in mesh with the planet gears and a low speed shaft or casing connected to the ring gear. Furthermore, the annulus is coupled to the ring gear and the low speed shaft or casing by means of flexible couplings, each of which comprises a plurality of flat springs.

Abstract: A method of operating a reverberatory furnace for copper smelting, wherein an oxygen fuel burner is provided in addition to the main fuel oil burners, and the oxygen content and flow rate of the oxygen-fuel gas mixture is so adjusted that the latent heat due to CO and H.sub.2 produced through the combustion in the combustion gas can be utilized at its maximum for increasing the smelting speed and SO.sub.2 content.