Microscope in-focus state detecting method and apparatus using image contrast detection
AssigneeHitachi Denshi Kabushiki Kaisha
InventorsShogo Kosuge, Takahiro Shimizu
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Abstract
A method and a device used in an optical microscope apparatus and for automatic focusing, and using an image contrast detection method which is not affected by noise. In order to remove a noise component, a contour component of an image picked up by the microscope is detected as a contour signal obtained by a difference between an original image and a delayed signal of the original image. A difference in level in maximum and minimum values of this contour signal is adopted as an image contrast signal. Such image contrast signals are produced at various microscope focusing direction positions. A position where a maximum image contrast signal is obtained is made to be an in-focus position.
Claims21
In a microscope apparatus wherein an image of a specimen from an optical microscope is converted to a video signal by an opto-electric converting sensor so that an image of said specimen in an in-focus state is displayed on a monitor, a method of detecting said in-focus state comprising the steps of:
- stepping said microscope along a focusing direction of said microscope to sequentially move said microscope;
- obtaining a difference between an original video signal of said specimen taken by said sensor at a predetermined microscope stop position in said stepping step and a delayed signal of said original video signal to generate a first contour-component signal;
- detecting a difference between maximum and minimum values of an amplitude of said first contour-component signal to obtain a first contrast signal;
- and
- adjusting a focus of said image based on said first contrast signal.
A method of displaying an image of a specimen from an optical microscope on a monitor, comprising the steps of:
- stepping said microscope along a focusing direction of said microscope to sequentially move said microscope;
- converting an image of said specimen from said microscope to a video signal by an opto-electric converting sensor;
- obtaining a difference between an original video signal of said specimen taken by said sensor at each of a plurality of predetermined microscope stop positions in said stepping step and a delayed signal of said original video signal to generate a first contour-component signal of said specimen;
- generating a first contrast signal representing a difference between maximum and minimum values of an amplitude of said first contour-component signal;
- adjusting a focus of said image based on said first contrast signal;
- and
- displaying said image of said specimen in said in-focus state on said monitor.
In a microscope apparatus wherein an image of a specimen from an optical microscope is converted to a video signal by an opto-electric converting sensor so that an image of said specimen in an in-focus state is displayed on a monitor, a method of detecting said in-focus state comprising the steps of:
- stepping a microscope up/down moving mechanism to sequentially move said microscope along a focusing direction;
- obtaining a difference between an original video signal of said specimen taken by said sensor at each of a plurality of predetermined microscope stop positions in said stepping step and a delayed signal of said original video signal to generate a first contour-component signal of said specimen;
- generating a first contrast signal representing a difference between maximum and minimum values of an amplitude of said first contour-component signal;
- detecting a maximum contrast signal from said first contrast signal;
- and
- fixing said microscope up/down moving mechanism at a microscope stop position where said maximum contrast signal is detected, to achieve said in-focus state.
In a microscope apparatus wherein an image of a specimen from an optical microscope in which an objective lens selected from among a plurality of objective lenses is used so that magnifying power of said microscope can be adjusted is converted to a video signal by an opto-electric converting sensor so that an image of said specimen in an in-focus state is displayed on a monitor, a method of setting said microscope in said in-focus state comprising the steps of:
- stepping a microscope up/down moving mechanism to sequentially move said microscope along a focusing direction;
- obtaining a difference between an original video signal of said specimen taken by said sensor at each of a plurality of predetermined microscope stop positions in said stepping step and a delayed signal of said original video signal to generate a first contour-component signal of said specimen;
- generating a first contrast signal representing a difference between maximum and minimum values of an amplitude of said first contour-component signal;
- detecting a maximum contrast signal from said first contrast signal at said predetermined microscope stop position;
- and
- fixing said microscope up/down moving mechanism at a microscope stop position where said maximum contrast signal is detected, to achieve said in-focus state,
- wherein delay time for said delayed signal of said original video signal is changed over in accordance with said selected objective lens.
In a microscope apparatus wherein an image of a specimen from an optical microscope is picked up and converted to a video signal by a television camera so that an image of the specimen in in-focus state is displayed on a display, a method of detecting the in-focus state comprising the steps of:
- stepping said microscope along a focusing direction of said microscope to sequentially move said microscope;
- obtaining a difference between an original video signal for each horizontal line taken by said television camera at each of a plurality of predetermined microscope stop positions in said stepping step and a delayed video signal for said horizontal line to generate a contour-component signal of said specimen;
- detecting a difference between a maximum and minimum values of an amplitude of said contour-component signal to obtain a first contrast signal for each horizontal line;
- summing said first contrast signal for each horizontal line to obtain a second contrast signal;
- and
- adjusting a focus of said image based on said second contrast signal.
An apparatus for detecting an in-focus state in a microscope apparatus including an optical microscope, comprising:
- an opto-electric converting sensor for converting an image of a specimen from said microscope to a video signal;
- a monitor for displaying said video signal;
- a moving apparatus for stepping said microscope along a focusing direction of said microscope to sequentially move said microscope;
- a contour-component signal extractor for obtaining a difference between said video signal of said specimen taken by said sensor at each of a plurality of predetermined microscope stop positions when said microscope is stepped and a delayed signal of said video signal to output said difference as a contour-component signal of said specimen;
- a contrast signal detector for outputting a first contrast signal representing a difference between maximum and minimum values of an amplitude of said contour-component signal;
- and
- a controller coupled with said moving apparatus for adjusting a focus of said image based on said first contrast signal.
Dependencies are inferred from the claim text.