Abstract A method of correcting a photoelectric microscope adapted to generate a photoelectric signal for detecting the end face position of a specimen in which the photoelectric signal is supplied to a pilot meter such, for example, as a conventional voltmeter or ammeter. The pilot meter has a scale with a level for generating the detecting pulse from a wave form shaping circuit marked thereon. The gain of the photoelectric signal is adjusted such that the ratio of the amplitude from the dark level to the level for generating the detecting pulse to the amplitude from the level for generating the detecting pulse to the bright level is made equal to a value defined by the change in the distribution of the quantity of light rays near the end face of the specimen. The level of the photoelectric signal may also be adjusted to obtain the same result. It is preferable to effect the adjustment of both the level and the gain of the photoelectric signal to obtain the ratio equal to the defined value. The desired ratio can be obtained by observing the deflection of an indication needle of the pilot meter. The specimen is moved to be scanned by a slit and a correct detecting pulse is generated at each instant when each edge of the end face of the specimen passes the center of the slit irrespective of possible change of the quantity of light near the end face of the specimen resulting from changes in configuration of and reflecting power at the specimen and in contrast, illumination, etc.
An apparatus for generating a photoelectric signal for detecting end face edges of specimens, comprising in combination: a photoelectric microscope for moving said edges of the specimens across the center of a slit; a photoelectric converter for converting the light ray after scanning said slit into a photoelectric pulse; a gain control device in series connection with said converter; a wave-form shaping circuit connected to said gain control device and producing a pulse for detecting said edges; and a pilot meter connected to the junction between said gain control device and said shaping circuit, having a uniformly graduated scale, and being provided along the latter with at least one first mark showing a level at which said detecting pulse is produced at the instant when said edges pass through said center of the slit; whereby said gain control device is set such that the ratio between first graduations VD'''' on said scale from a dark level to said first mark, on the one hand, and second graduations VB'''' from said first mark to a bright level, on the other hand, is equal to VD''''/VB'''' inherent in the specimen, said ratio being predetermined and listed beforehand in a table.
Claim 2
Independent Claim
198 words
An apparatus for generating a photoelectric signal for detecting end face edges of specimens, comprising in combination: a photoelectric microscope for moving said edges of the specimens across the center of a slit; a photoelectric converter for converting the light ray after scanning said slit into a photoelectric pulse; a gain control device in series connection with said converter; a wave-form shaping circuit connected to said gain control device and producing a pulse for detecting said edges; and a pilot meter connected to the junction between said gain control device and said shaping circuit, having a uniformly graduated scale, and being provided along the latter with at least one first mark showing a level at which said detecting pulse is produced at the instant when said edges pass through said center of the slit; whereby said gain control device is set such that the ratio between first graduations VD'''' on said scale from a dark level to said first mark, on the one hand, and second graduations VB'''' from said first mark to a bright level, on the other hand, is equal to VD''''/VB'''' inherent in the specimen, said ratio being predetermined and listed beforehand in a table.
Claim 3
Dependent Claim
130 words
The apparatus as defined in claim 1, further comprising a level control device connected between said converter and said gain control device, and wherein said pilot meter is provided along said scale with a second mark showing a standard dark level and with a plurality of further marks showing bright levels inherent in a plurality of the specimens, whereby said level control device and said gain control device are set such that a second ratio between third graduations VD from said second mark to said first mark, on the one hand, and fourth graduations VB from said first mark to one of said further marks, on the other hand, is equal to VD/VB inherent in one of the specimens, said second ratio being predetermined and listed beforehand in said table.