Optical assembly

Patent metadata

Field	Value
Publication number	US-10353209-B2
Application number	US-201615130479-A
Country	US
Kind code	B2
Filing date	Apr 15, 2016
Priority date	Apr 17, 2015
Publication date	Jul 16, 2019
Grant date	Jul 16, 2019

Abstract

Optical assembly containing a) at least two pairs of dichroic beamsplitting elements grouped together such that first sides of these elements are parallel and immediately adjacent to one another and to a predetermined line, and b) two optical lenses disposed such that light transmitted through the lenses towards the beamsplitting element passes through the elements without being scattered at the first sides. Optionally, a first dichroic beamsplitting element in a first pair and a first dichroic element in a second pair have equal optical properties. Imaging probe—for example, a laparoscope—employing such optical assembly.

First claim

What is claimed is:

1. An optical assembly comprising:
at least two pairs of dichroic beamsplitting elements grouped together such that first sides of the first and second dichroic beamsplitting elements in each of the at least two pairs are parallel and immediately adjacent to one another and to a predetermined line,
two optical lenses disposed such that light transmitted through said lenses towards said at least two pairs of dichroic beamsplitting elements passes through each of elements from said at least two pairs of the dichroic beamsplitting elements, and
at least two image sensors, each of the at least two image sensors positioned to receive said light that has passed, in operation of the optical assembly, through both a) a pair of the at least two pairs of the dichroic beamsplitting elements and b) one of the two optical lenses.

2. An optical assembly according to claim 1 , wherein a first dichroic beamsplitting element in a first pair of the at least two pairs of dichroic beamsplitting elements and a first dichroic beamsplitting element in a second pair of the at least two pairs of dichroic beamsplitting elements have equal optical properties.

3. An optical assembly according to claim 1 , wherein said light includes infrared light and wherein one of the at least two image sensors is configured to detect said infrared light.

4. An optical assembly according to claim 1 , wherein a dichroic beamsplitting element from said at least two pairs of dichroic beamsplitting elements is defined on a facet of an optical prism.

5. An optical assembly comprising:
first, second, third, and fourth dichroic beamsplitter elements, an area of each of the dichroic beamsplitter element bound by corresponding first, second, third, and fourth polygons,
wherein said first, second, third, and fourth dichroic beamsplitter elements are disposed such that first sides of each of said first, second, third, and fourth polygons extend along a predetermined line and are immediately adjacent to one another; and

two optical lenses, each having a corresponding optical axis that is transverse to the predetermined line and passes through bodies of at least two polygons of said first second, third, and fourth polygons at points each of which is spatially separated by a distance from corresponding primary sides of the at least two polygons;
said lenses disposed on the same side with respect to a group of said first, second, third, and fourth dichroic beamsplitter elements;
and at least two image sensors positioned to receive light that has passed through both a) each of the first, second, third, and fourth dichroic beamsplitter elements and b) at least one of the optical lenses.

6. An optical assembly according to claim 5 , wherein the distance is equal to or larger than a radius of an optical lens.

7. An optical assembly according to claim 5 , wherein optical axes of the two optical lenses are parallel to one another.

8. An optical assembly according to claim 5 , wherein a dichroic beamsplitter element from said first, second, third, and fourth dichroic beamsplitter elements is defined on a facet of an optical prism, and wherein an apex of said optical prism defines the first side of said dichroic beamsplitter element from said first, second, third, and fourth dichroic beamsplitter elements.

9. An optical assembly according to claim 5 , wherein the first, second, third, and fourth dichroic beamsplitter elements are formed on facets of first, second, and third prisms, wherein an apex of the first prism defines the predetermined line, wherein the apexes of the second and third prisms define first sides of the corresponding first, second, third, and fourth polygons.

10. An optical assembly according to claim 5 ,
wherein the first and second dichroic beamsplitter elements are formed on facets of respectively-corresponding first and second prisms,
wherein each of said at least two image sensors is disposed at a facet of a base of a corresponding prism, from the first and second prisms, to intersect one of partial beams of light that are produced, in operation, from light delivered by a lens from the two optical lenses towards the group of said first, second, third, and fourth dichroic beamsplitter elements.

11. An optical assembly according to claim 5 , further comprising a housing configured to enclose said first, second, third, and fourth dichroic elements and the two optical lenses, optical axes of the two optical lenses being parallel to one another, the optical system configured as a laparoscope with the two optical lenses disposed at a distal end thereof.

12. An optical assembly according to claim 5 , wherein those of first, second, third, and fourth dichroic beamsplitter elements that are intersected by an axis of an optical lens from the two optical lenses, are configured to spatially split a beam of light that has passed through said optical lens into at least three partial beams having different spectra.

13. An optical assembly according to claim 12 , wherein each of said at least two image sensors is disposed in optical communication with at least one of the two lenses to intersect a respectively corresponding beam of the at least three partial beams, one of the two image sensors being devoid of a Bayer filter.

14. An optical assembly according to claim 12 , wherein a first of the different spectra includes visible wavelengths and a second of the different spectra includes wavelengths exceeding 1200 nm.

15. An optical assembly according to claim 5 , wherein a surface of at least one of said first, second, third, and fourth dichroic beamsplitting elements is curved.

16. An optical assembly according to claim 5 , wherein said light includes infrared light and wherein one of the at least two image sensors is configured to detect said infrared light.

17. An optical assembly according to claim 5 ,
further comprising a third image sensor,
wherein the third dichroic beamsplitter element is formed on a facet of a third prism, an apex of the first prism defining the predetermined line, the apexes of the second and third prisms defining first sides of the corresponding first, second, and third polygons,
wherein each of said at least two image sensors and said third image sensor is disposed at a facet of a base of a corresponding prism from the first, second, and third prisms.

18. A method for operating an optical assembly, the method comprising:
transmitting light from outside of the optical assembly through two lenses of said assembly towards at least four dichroic beamsplitter elements of said assembly, wherein said assembly is disposed within a cylindrical housing,
wherein an operating surface of each of said at least four dichroic beamsplitter elements is bound by a respective polygon,
wherein first sides of all polygons are parallel to a predetermined line and immediately adjacent to one another, and
wherein an optical axis of each of the two lenses is transverse to the predetermined line, is spaced therefrom by a distance, and intersects at least bodies of at least two of polygons that bound operating surfaces of the at least four dichroic beamsplitter elements; and

reflecting said light recevied from at least two of said at least four dichroic beamsplitter elements to form at least first and second reflected portions of light and a transmitted portion of light, and
receiving each of said reflected and transmitted portions of light by a corresponding optical detector from at least three optical detectors of the optical assembly.

19. A method according

Assignees

• Nikon Corp

Inventors

• Rosa Matthew

Classifications

• G02B27/149

  using crossed beamsplitting surfaces, e.g. cross-dichroic cubes or X-cubes · CPC title

• G02B27/1013 Primary

  for colour or multispectral image sensors, e.g. splitting an image into monochromatic image components on respective sensors (spectral imaging systems G01J) · CPC title

• G03B17/17

  with reflectors arranged in beam forming the photographic image, e.g. for reducing dimensions of camera · CPC title

• G02B23/2415

  Stereoscopic endoscopes · CPC title

• G03B33/04

  by four or more separation records · CPC title