Abstract: Object: provide an accurate monitor of light of even intensity light. Construction: A beam splitter (4) being fixed on a base (1) in the path of a main beam (2) of a light system, a reflecting mirror (5) being fixed on a side of the beam splitter (4), an inlet 6a of an integrating sphere (6) is provided at an opposite side of the beam splitter (4), and a light sensor (8) is provided at a reflecting surface of the integrating sphere (6).

Abstract: An apparatus for measuring a dimension or aspect of a figure, such as a linear planimeter or a polar planimeter, for measuring a size and shape of a figure and having a calibration mode. The apparatus includes a carriage supported on a pair of rollers for movement along an axis. One end of a measuring lever is pivotally mounted to the carriage. A tracing member having a magnifying lens for tracing a figure is provided on the other of the measuring lever. A computer having a calibrating mode changing switch and a correction value recording switch are provided on the carriage. To calibrate the apparatus, the apparatus is switched into the calibrating mode by the calibrating mode changing switch and correction values are calculated based on a reference figure. Each correction value is stored in a nonvolatile memory of the computer.

Abstract: A device for measuring a figure. The measuring device includes an auxiliary tracer to obtain measurement coordinates when a measuring lever of the measuring device is beyond a predetermined rotatable range. The auxiliary tracer functions to increase the measurable range of the measuring device without having to increase the over-all length of the measuring device. The device includes a body having a pair of wheels with a measuring lever extending therefrom and having a main tracer. An auxiliary tracer is provided on an auxiliary arm extending from the measuring lever. Data from either the main tracer or the auxiliary tracer can be processed by a processor to measure the figure.

Abstract: An apparatus for measuring figures having circular arc portions by obtaining coordinates of a starting point, an ending point and an intermediate point of each circular arc. The measuring apparatus measures at least one of coordinates or an area of a figure. The measuring apparatus has a main body and a measuring lever. The main body has a pair of rollers that drive the measuring apparatus in a running direction. The measuring lever is pivotally supported on the main body so as to be rotatable in a clockwise and counter-clockwise direction. The measuring lever includes a tracer, a point key, and an arc key. The point key is manipulated when the measuring lever is at the starting point of the circular arc portion. The arc key is manipulated when the measuring lever is at the intermediate point. The point key again is manipulated when the measuring lever is at the ending point. By obtaining these three points, a parameter of a figure, including the circular arc portion, can be determined.