Dual viewfinder for observing device

Patent metadata

Field	Value
Publication number	US-12085706-B2
Application number	US-202218068659-A
Country	US
Kind code	B2
Filing date	Dec 20, 2022
Priority date	Dec 26, 2021
Publication date	Sep 10, 2024
Grant date	Sep 10, 2024

Abstract

A viewfinder with which an observing or image-recording device, such as a spotting scope or image-recording apparatus, is intended to be equipped, the observing device being configured to produce an image of an observed scene. The viewfinder allows a first image, representative of the observed scene, and a second image, different from the first image, to be displayed, the first image and the second image being juxtaposed with respect to each other. The observing device includes a first optical system and a second optical system configured to propagate the first image and the second image towards the eye of a user, along two distinct axes of propagation, respectively. The optical systems are such that passage from observing one image to observing the other image is achieved through simple natural rotation of the eye.

First claim

The invention claimed is:

1. A viewfinder, configured to be placed facing an eye of a user of an observing device, the observing device comprising an observation objective intended to form an image of an observed scene, the viewfinder comprising:
a device for forming a first image, representative of the observed scene;
a first optical system, coupled to the device for forming the first image, and arranged to propagate the first image to a first exit pupil, about a first optical axis, the light rays forming the first image reaching the first exit pupil by propagating about the first optical axis;

wherein the viewfinder comprises:
a secondary display, emitting a second image, different from the first image;
a second optical system, lying between the secondary display and a second exit pupil, about a second optical axis, inclined with respect to the first optical axis, the second optical system being configured to propagate the second image to the second exit pupil, the light rays forming the second image reaching the second exit pupil by propagating about the second optical axis;

and wherein:
the first exit pupil and the second exit pupil are tangent to the same spherical surface, the diameter of which is comprised between 1.5 cm and 3 cm, wherein the spherical-surface diameter corresponds to the ocular diameter;
the first optical axis and the second optical axis converge, to a point of convergence, corresponding to the centre of said spherical surface, wherein the point of convergence is located in the eye of the user such that the user may view
the first image when the eye is oriented along the first optical axis;
the second image when the eye is oriented along the second optical axis.

2. The viewfinder according to claim 1 , wherein the first optical axis and the second optical axis are coplanar and lie in a vertical or horizontal plane.

3. The viewfinder according to claim 1 , wherein:
the first image and the second image, viewed respectively at the first and at the second exit pupil, extend:
about a longitudinal axis, defining a width;
parallel to a lateral axis, defining a height;
the second axis and the first axis lie in a plane parallel to the lateral axis, wherein the first image and the second image are juxtaposed while being aligned with respect to each other parallel to the lateral axis;
or the second axis and the first axis lie in a plane parallel to the longitudinal axis, wherein the first image and the second image are juxtaposed while being aligned with respect to each other parallel to the longitudinal axis.

4. The viewfinder according to claim 1 , wherein the first optical axis and the second optical axis are inclined with respect to each other by an angle of inclination smaller than 40°.

5. The viewfinder according to claim 1 , wherein:
the observation objective forms the image of the observed scene about an optical axis of observation;
the first optical axis is parallel to the optical axis of observation.

6. The viewfinder according to claim 1 , wherein:
the observing device is an image-capturing apparatus, comprising an image sensor, the image sensor being configured to acquire the image of the observed scene, formed by the observation objective;
the secondary display is connected to the image sensor, so that wherein the second image is formed from the image acquired by the image sensor.

7. The viewfinder according to claim 6 , wherein:
the device for forming the first image is a splitter, arranged to be placed between the observation objective and the image sensor, the splitter being oriented so as to steer the image of the observed scene, focused by the objective, towards the first optical system;
the first optical system extends from the splitter.

8. The viewfinder according to claim 6 , wherein:
the device for forming the first image is an auxiliary objective, different from the observation objective, intended to form an image of the observed scene;
the first optical system extends from the auxiliary objective.

9. The viewfinder according to claim 6 , wherein:
the device for forming the first image is an auxiliary display, intended to display an image of the observed scene;
the first optical system extends from the auxiliary display.

10. The viewfinder according to claim 6 , wherein the image-capturing apparatus comprises a unit for controlling the image sensor, and wherein the viewfinder comprises:
a display, connected to the control unit and configured to display a third image;
a third optical system, configured to propagate the third image to the first optical system.

11. The viewfinder according to claim 1 , wherein the first optical system extends to a first exit dioptric interface, the first exit dioptric interface being positioned at a distance larger than or equal to 15 mm from the first exit pupil.

12. The viewfinder according to claim 1 , wherein the second optical system extends to a second exit dioptric interface, the second exit dioptric interface being positioned at a distance larger than or equal to 15 mm from the second exit pupil.

13. The viewfinder according to claim 1 , wherein
the observing device is magnifying, the first optical system and the observing objective being one and the same;
the image sensor is placed on a peripheral device, separate from the observing device;
the secondary display is configured to display an image acquired by the image sensor, optionally after application of an image-processing operation.

14. An observing device, comprising an observation objective, intended to form an image of an observed scene, about an optical axis of observation, the observing device comprising the viewfinder according to claim 1 .

15. The observing device according to claim 14 , the observing device being a camera comprising an image sensor, the image sensor being configured to acquire the image of the observed scene, formed by the observation objective.

16. The observing device according to claim 14 , the observing device being magnifying, the first optical system and the observation objective being one and the same.

Assignees

• Commissariat Energie Atomique

Inventors

• Charriere Simon
• Joly Pierre

Classifications

• G02B27/14

  operating by reflection only · CPC title

• G02B27/106

  for splitting or combining a plurality of identical beams or images, e.g. image replication · CPC title

• H04N23/53

  of electronic viewfinders, e.g. rotatable or detachable · CPC title

• H04N23/633

  for displaying additional information relating to control or operation of the camera · CPC title

• G02B23/105

  Sighting devices with light source and collimating reflector (reflecting sights for small arms having light source F41G1/34) · CPC title