US3798449A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic microscope focussing device
Assignee: Individual
•
Filing: 1973-05-21
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Granted: 1974-03-19
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Expires: 1993-05-21
Abstract
Abstract A microscope is provided with an optical grating in the light path of the objective lens at a predetermined distance from the object to focus an image of an object portion thereon. At least one photoelectric sensing device is arranged behind the grating for receiving light transmitted from the objective via the objective lens and for generating an electric control responsive to the deviation of the grating from the exact focussing position. A servo system utilizes the control signal for displacing the object along the optical axis in dependence on the signal so that the image of the object is automatically focussed on the grating. Means are provided for optionally varying the distance between the object and the grating, thereby bringing different object planes into focus.
Inventors
- 👤 G Reinheimer
- 👤 L Leitz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:49
CPC Classifications
G; G02; G02B; G02B21/00; G02B21/24; G02B21/241
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
198 words
An arrangement for automatically focussing a microscope on to a pre-selected one of a plurality of mutually displaced parallel planes in an object, the arrangement comprising: a. a microscope objective lens to focus an image of an object portion located in a predetermined object plane in a predetermined image plane of the microscope; b. a stage for supporting the object imaged by the microscope: c. an optical grating for receiving light transmitted from the object via the objective lens; d. at least one photo-electric sensing device responsive to light transmitted via the grating; e. displacement means for effecting relative displacement between the grating and the predetermined image plane along the optical axis of the objective lens to select a different one of the object planes for focussing by the microscope lens; f. means for deriving from the or each sensing device an electrical control signal responsive to the extent of said relative displacement; and g. a servo system including means for so displacing the stage along the optical axis in response to the control signal that an image of an object portion in an object plane displaced along said axis by said extent is focussed on said grating.
Claim 2
Dependent Claim
198 words
An arrangement for automatically focussing a microscope on to a pre-selected one of a plurality of mutually displaced parallel planes in an object, the arrangement comprising: a. a microscope objective lens to focus an image of an object portion located in a predetermined object plane in a predetermined image plane of the microscope; b. a stage for supporting the object imaged by the microscope: c. an optical grating for receiving light transmitted from the object via the objective lens; d. at least one photo-electric sensing device responsive to light transmitted via the grating; e. displacement means for effecting relative displacement between the grating and the predetermined image plane along the optical axis of the objective lens to select a different one of the object planes for focussing by the microscope lens; f. means for deriving from the or each sensing device an electrical control signal responsive to the extent of said relative displacement; and g. a servo system including means for so displacing the stage along the optical axis in response to the control signal that an image of an object portion in an object plane displaced along said axis by said extent is focussed on said grating.
Claim 3
Dependent Claim
25 words
An arrangement as claimed in claim 1, wherein the means for effecting said relative displacement comprises means to displace the grating along the optical axis.
Claim 4
Dependent Claim
43 words
An arrangement as claimed in claim 1, wherein the means for effecting said relative displacement comprises an optical component disposed in the path traversed by light received only by the grating, said optical component being adjustable to vary the length of said path.
Claim 5
Dependent Claim
36 words
An arrangement as claimed in claim 3, wherein the optical component comprises a double optical wedge assembly, the wedges being relatively displaceable in a direction transverse of said axis to vary the length of said path.
Claim 6
Dependent Claim
54 words
An arrangement as claimed in claim 1, comprising means to periodically displace the grating in a plane perpendicular to the axis to cause the or each photo-electric sensing device to provide respective alternating electrical signals responsive to the extent of the relative displacement between the grating and the image formed by the objective lens.
Claim 7
Dependent Claim
14 words
An arrangement as claimed in claim 5, comprising a pair of photo-electric sensing devices.
References Cited (Backward Citations)
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US2968994A
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US3398665A
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US3555280A
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US3450018A
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US3721827A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-18 | 1977-09-17 | 1978-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-18 | 1981-09-17 | 1982-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-18 | 1985-09-17 | 1986-03-19 | $7700.00 | Window Closed / Lapsed |