Focusing methods and apparatuses, and photographing devices

• US 10,447,913 B2
• Filed: 03/04/2016
• Issued: 10/15/2019
• Est. Priority Date: 03/24/2015
• Status: Active Grant

• Current Assignee: Beijing Zhigu RUI TUO Tech Company Limited
• Original Assignee: Beijing Zhigu RUI TUO Tech Company Limited
• Inventors: Du, Lin
• Primary Examiner(s): Berhan, Ahmed A
• Application Number:
  US15/559,189
• Publication Number:
  US 20180084186A1
• Time in Patent Office: 1,320 Days
• CPC Class Codes: G02B 7/38 measured at different points on the optical axis , e.g. focussing on two or more planes and comparing image data
• CPC Class Codes: H04N 23/673 based on contrast or high frequency components of image signals, e.g. hill climbing method
• CPC Class Codes: H04N 23/675 comprising setting of focusing regions

Abstract

The present application discloses various focusing methods and apparatuses, and various photographing devices. The focusing method includes: controlling deformation of an image sensor so that reference points of at least two imaging sub-areas of the image sensor after the deformation form a first relative position relationship in a staggered arrangement along a depth direction; acquiring contrast data of a sampling image of an object in the at least two imaging sub-areas; and determining and/or adjusting, according to at least the first relative position relationship and the contrast data, a focusing state of the image sensor. The present application can improve a speed and/or accuracy for determining and/or adjusting the focusing state of the image sensor.

Claims

1. A focusing method, comprising:

controlling deformation of an image sensor so that reference points of at least two imaging sub-areas of the image sensor after the deformation form a first relative position relationship in a staggered arrangement along a depth direction;

acquiring contrast data of a sampling image of an object in the at least two imaging sub-areas; and

determining and/or adjusting, according to at least the first relative position relationship and the contrast data, a focusing state of the image sensor;

wherein the determining and/or adjusting, according to at least the first relative position relationship and the contrast data, a focusing state of the image sensor comprises;

determining, according to at least the first relative position relationship and the contrast data, second relative position information, which is in the depth direction, depth scopes that correspond to the at least two imaging areas relative to a target in focus depth position that corresponds to the object; and

determining and/or adjusting, according to at least the second relative position information, the focusing state of the image sensor.

2. The method of claim 1, wherein the determining, according to at least the first relative position relationship and the contrast data, second relative position information in the depth direction of depth scopes that correspond to the at least two imaging areas relative to a target in focus depth position that corresponds to the object comprises:

determining, in response to that the contrast data corresponding to the at least two imaging sub-areas presents a unidirectional change trend, that the target in focus depth position is out of the depth scopes corresponding to the at least two imaging sub-areas.

3. The method of claim 2, wherein the determining, in response to that the contrast data corresponding to the at least two imaging sub-areas presents a unidirectional change trend, that the target in focus depth position is out of the depth scopes corresponding to the at least two imaging sub-areas comprises:

determining, in response to that the contrast data corresponding to the at least two imaging sub-areas presents a first unidirectional change trend matching the first relative position relationship, that the target in focus depth position is at a depth position behind the depth scopes corresponding to the at least two imaging subareas.

4. The method of claim 2, wherein the determining, in response to that the contrast data corresponding to the at least two imaging sub-areas presents a unidirectional change trend, that the target in focus depth position is out of the depth scopes corresponding to the at least two imaging sub-areas comprises:

determining, in response to that the contrast data corresponding to the at least two imaging sub-areas presents a second unidirectional change trend opposite to the first relative position relationship, that the target in focus depth position is at a depth position in front of the depth scopes corresponding to the at least two imaging sub-areas.

5. The method of claim 1, wherein the determining, according to at least the first relative position relationship and the contrast data, second relative position information, which is in the depth direction, of depth scopes that correspond to the at least two imaging areas relative to a target in focus depth position that corresponds to the object comprises:

determining, in response to that the contrast data corresponding to the at least two imaging sub-areas presents a non-unidirectional change trend, that the target in focus depth position is between the depth scopes corresponding to the at least two imaging sub-areas.

6. The method of claim 1, wherein the adjusting, according to at least the second relative position information, the focusing state of the image sensor comprises:

adjusting, according to at least the second relative position information, focusing parameters of a photographing device comprising the image sensor so that an imaging plane position of the image sensor approaches or coincides with the target in focus depth position after the focusing parameters are adjusted.

7. The method of claim 1, wherein before the controlling deformation of the image sensor, the method further comprises:

determining a deformation degree of the image sensor, wherein maximum deformation along the depth direction of the at least two imaging sub-areas corresponding to an initial adjustment phase of an adjustment process of the focusing state is greater than the maximum deformation along the depth direction of the at least two imaging sub-areas corresponding to other phases of the adjustment process of the focusing state.

8. The method of claim 7, wherein from the initial adjustment phase of the adjustment process of the focusing state to a convergence phase, the maximum deformation along the depth direction of the at least two imaging subareas corresponding to the phases progressively decreases in sequence.

9. The method of claim 1, wherein before the controlling deformation of the image sensor, the method further comprises:

determining, according to a preview image of the object, a focus area; and

determining, according the focus area, the at least two imaging sub-areas, wherein the at least two imaging sub-areas respectively correspond to at least two focus sub-areas comprised in the focus area.

10. The method of claim 9, wherein the determining, according to the focus area, the at least two imaging subareas comprises:

determining, according to content of the focus area, a quantity of the imaging sub-areas.

11. The method of claim 10, wherein the quantity of the imaging sub-areas corresponding to the focus area whose content has more details is greater than the quantity of the imaging sub-areas corresponding to the focus area whose

content has fewer details.

12. A non-transitory computer readable storage apparatus, storing at least one executable instruction executable by a processor of a photographing device to cause the photographing device to perform operations comprising:

controlling deformation of an image sensor so that reference points of at least two imaging sub-areas of the image sensor after the deformation form a first relative position relationship in a staggered arrangement along a depth direction;

acquiring contrast data of a sampling image of an object in the at least two imaging sub-areas; and

determining and/or adjusting, according to at least the first relative position relationship and the contrast data, a focusing state of the image sensor;

wherein the determining and/or adjusting, according to at least the first relative position relationship and the contrast data, a focusing state of the image sensor comprises;

determining, according to at least the first relative position relationship and the contrast data, second relative position information, which is in the depth direction, of depth scopes that correspond to the at least two imaging areas relative to a target in focus depth position that corresponds to the object; and

determining and/or adjusting, according to at least the second relative position information, the focusing state of the image sensor.

13. The non-transitory computer readable storage apparatus of claim 12, wherein the determining, according to at least the first relative position relationship and the contrast data, second relative position information, which is in the depth direction, of depth scopes that correspond to the at least two imaging areas relative to a target in focus depth position that corresponds to the object comprises:

determining, in response to that the contrast data corresponding to the at least two imaging sub-areas presents a unidirectional change trend, that the target in focus depth position is out of the depth scopes corresponding to the at least two imaging sub-areas.

14. The non-transitory computer readable storage apparatus of claim 13, wherein the determining, in response to that the contrast data corresponding to the at least two imaging sub-areas presents a unidirectional change trend, that the target in focus depth position is out of the depth scopes corresponding to the at least two imaging sub-areas comprises:

determining, in response to that the contrast data corresponding to the at least two imaging sub-areas presents a first unidirectional change trend matching the first relative position relationship, that the target in focus depth position is at a depth position behind the depth scopes corresponding to the at least two imaging sub-areas.

15. The non-transitory computer readable storage apparatus of claim 13, wherein the determining, in response to that the contrast data corresponding to the at least two imaging sub-areas presents a unidirectional change trend, that the target in focus depth position is out of the depth scopes corresponding to the at least two imaging sub-areas comprises:

determining, in response to that the contrast data corresponding to the at least two imaging subareas presents a second unidirectional change trend opposite to the first relative position relationship, that the target in focus depth position is at a depth position in front of the depth scopes corresponding to the at least two imaging sub-areas.

16. The non-transitory computer readable storage apparatus according to claim 12, wherein the determining, according to at least the first relative position relationship and the contrast data, second relative position information, which is in the depth direction, of depth scopes that correspond to the at least two imaging areas relative to a target in focus depth position that corresponds to the object comprises:

determining, in response to that the contrast data corresponding to the at least two imaging sub-areas presents a non-unidirectional change trend, that the target in focus depth position is between the depth scopes corresponding to the at least two imaging subareas.

17. The non-transitory computer readable storage apparatus of claim 12, wherein the adjusting, according to at least the second relative position information, the focusing state of the image sensor comprises:

adjusting, according to at least the second relative position information, focusing parameters of a photographing device comprising the image sensor so that an imaging plane position of the image sensor approaches or coincides with the target in focus depth position after the focusing parameters are adjusted.

18. The non-transitory computer readable storage apparatus of claim 12, wherein the operations further comprises:

determining a deformation degree of the image sensor, wherein maximum deformation along the depth direction of the at least two imaging sub-areas corresponding to an initial adjustment phase of an adjustment process of the focusing state is greater than the maximum deformation along the depth direction of the at least two imaging sub-areas corresponding to other phases of the adjustment process of the focusing state.

19. The non-transitory computer readable storage apparatus of claim 18, wherein from the initial adjustment phase of the adjustment process of the focusing state to a convergence phase, the maximum deformation along the depth direction of the at least two imaging subareas corresponding to the phases progressively decreases in sequence.

20. The non-transitory computer readable storage apparatus of claim 12, wherein the operations further comprises:

determining, according to a preview image of the object, a focus area; and

determining, according the focus area, the at least two imaging sub-areas, wherein the at least two imaging sub-areas respectively correspond to at least two focus sub-areas comprised in the focus area.

21. The non-transitory computer readable storage apparatus of claim 20, wherein the determining, according the focus area, the at least two imaging sub-areas comprises:

determining, according content of the focus area, a quantity of the imaging sub-areas.

22. The non-transitory computer readable storage apparatus of claim 21, wherein the quantity of the imaging sub-areas corresponding to the focus area whose content has more details is greater than the quantity of the imaging sub-areas corresponding to the focus area whose content has fewer details.

23. A photographing device, comprising:

a photographing optical system, a deformable image sensor, and the non-transitory computer readable storage apparatus according to claim 12.

24. The photographing device of claim 23, wherein the image sensor comprises a flexible image sensor.

25. The photographing device of claim 23, wherein the image sensor comprises multiple imaging sub-areas in an array distribution, and the at least two imaging sub-areas are connected by a deformable connection component.

26. A system, comprising:

a processor; and

a memory storing computer executable instructions, the processor being connected to the memory through a communication bus, and configured to execute the instructions to cause the system to perform;

controlling deformation of an image sensor so that reference points of at least two imaging sub-areas of the image sensor after the deformation form a first relative position relationship in a staggered arrangement along a depth direction;

acquiring contrast data of a sampling image of an object in the at least two imaging sub-areas; and

determining and/or adjusting, according to at least the first relative position relationship and the contrast data, a focusing state of the image sensor;

wherein the determining and/or adjusting, according to at least the first relative position relationship and the contrast data, a focusing state of the image sensor comprises;

determining, according to at least the first relative position relationship and the contrast data, second relative position information, which is in the depth direction, depth scopes that correspond to the at least two imaging areas relative to a target in focus depth position that corresponds to the object; and

determining and/or adjusting, according to at least the second relative position information, the focusing state of the image sensor.