Surgical microscope and method implemented with the surgical microscope

Patent metadata

Field	Value
Publication number	US-10440256-B2
Application number	US-201816174086-A
Country	US
Kind code	B2
Filing date	Oct 29, 2018
Priority date	Oct 30, 2017
Publication date	Oct 8, 2019
Grant date	Oct 8, 2019

Abstract

A surgical microscope, in particular an ophthalmic surgical microscope, includes a microscope imaging optical unit for imaging an object to be observed in an image plane along an optical imaging beam path, which passes through the microscope imaging optical unit, and a camera, which captures imaging of the object in the image plane. Further, the surgical microscope includes an optical wavefront encoding element that is positioned or positionable in the optical imaging beam path to influence an imaging light wavefront in the optical imaging beam path in such a way that a depth of field of the imaging of the object through the microscope imaging optical unit with the wavefront encoding element is reduced in relation to the depth of field of the imaging of the object through the microscope imaging optical unit without the wavefront encoding element.

First claim

The invention claimed is:

1. A surgical microscope comprising:
a microscope imaging optical unit configured to image an object to be examined in an image plane along an optical imaging beam path passing through the microscope imaging optical unit;
a camera configured to capture an image of the object in the image plane;
an optical wavefront encoding element that is positioned or positionable in the optical imaging beam path, wherein the optical wavefront encoding element is configured to influence an imaging light wavefront in the optical imaging beam path, wherein the microscope imaging optical unit images the object to be examined in the image plane with a depth of field when the optical wavefront encoding element is not positioned in the optical imaging beam path, and wherein the microscope imaging optical unit images the object to be examined in the image plane with a reduced depth of field when the optical wavefront encoding element is positioned in the optical imaging beam path;
a computer unit configured to calculate an image with the reduced depth of field for further processing from an image of the object with the reduced depth of field captured by the camera; and
an autofocus system configured to receive data from the computer unit to automatically focus the image of the object with the reduced depth of field.

2. The surgical microscope according to claim 1 , further comprising:
an image rendering unit configured to display at least one of the image of the object with the depth of field or the image of the object with the reduced depth of field on a screen.

3. The surgical microscope according to claim 1 , wherein the optical wavefront encoding element can be brought into the optical imaging beam path and to be subsequently removed from the optical imaging beam path.

4. The surgical microscope according to claim 1 , wherein the optical wavefront encoding element is positioned or positionable at a point in the optical imaging beam path at which the optical imaging beam path is parallel; or the optical wavefront encoding element is positioned or positionable in, or in the vicinity of, a pupil plane; or the optical wavefront encoding element is positioned or positionable in, or in the vicinity of, a plane conjugate to the pupil plane in the optical imaging beam path.

5. The surgical microscope according to claim 1 , wherein the microscope imaging optical unit further comprises:
a zoom system, wherein the optical imaging beam path is parallel on an output-side of the zoom system, and wherein the optical wavefront encoding element is positioned or positionable downstream of the zoom system, as seen in a direction of the optical imaging beam path.

6. The surgical microscope according to claim 1 , wherein the optical wavefront encoding element is a phase-shifting element.

7. The surgical microscope according to claim 1 , wherein the reduced depth of field is less than 1 mm.

8. The surgical microscope according to claim 1 , wherein the reduced depth of field is reduced by a factor in a range of from 1.5 to 5 in relation to the depth of field.

9. A method for measuring an object with a surgical microscope, the method comprising:
providing a surgical microscope including:
a microscope imaging optical unit configured to image an object to be examined in an image plane along an optical imaging beam path passing through the microscope imaging optical unit;
a camera configured to capture an image of the object in the image plane;
an optical wavefront encoding element that is positioned or positionable in the optical imaging beam path;
a computer unit configured to calculate an image with a reduced depth of field for further processing from an image of the object with the reduced depth of field captured by the camera; and
an autofocus system configured to receive data from the computer unit to automatically focus the image with the reduced depth of field;

arranging an object to be examined on an object side of the microscope imaging optical unit;
positioning the optical wavefront encoding element in the optical imaging beam path;
imaging the object to be examined in the image plane;
capturing an image with a reduced depth of field of the object to be examined with the camera for further processing; and
automatically focusing the image with the reduced depth of field of the object to be examined.

10. The surgical microscope according to claim 1 , wherein the surgical microscope is an ophthalmic surgical microscope.

11. The surgical microscope according to claim 1 , wherein the reduced depth of field is less than 0.75 mm.

12. The surgical microscope according to claim 1 , wherein the reduced depth of field is approximately 0.3 mm.

13. The method according to claim 9 , wherein the surgical microscope is an ophthalmic surgical microscope.

Assignees

• Zeiss Carl Meditec Ag

Inventors

• Reimer Peter
• Beder Christian

Classifications

• H04N23/959 Primary

  by adjusting depth of field during image capture, e.g. maximising or setting range based on scene characteristics · CPC title

• A61B3/13

  Ophthalmic microscopes · CPC title

• G02B21/0012

  Surgical microscopes (counterbalanced structures for surgical microscopes G02B7/001) · CPC title

• A61B3/1015

  for wavefront analysis · CPC title

• A61B90/361

  Image-producing devices, e.g. surgical cameras · CPC title