APPARATUS AND METHOD FOR ACQUIRING INFORMATION ABOUT LIGHT-FIELD DATA

• US 20140063332A1
• Filed: 09/04/2012
• Published: 03/06/2014
• Est. Priority Date: 09/04/2012
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Miyawaki, Mamoru
• Granted Patent: US 9,036,080 B2
• Time in Patent Office: Days
• US Class Current: 348/360
• CPC Class Codes: G03B 13/20 Rangefinders coupled with focusing arrangements, e.g. adjustment of rangefinder automatically focusing camera
• CPC Class Codes: G03B 35/10 having single camera with stereoscopic-base-defining system
• CPC Class Codes: H04N 23/60 Control of cameras or camera modules
• CPC Class Codes: H04N 23/951 by using two or more images to influence resolution, frame rate or aspect ratio
• CPC Class Codes: H04N 23/957 Light-field or plenoptic cameras or camera modules
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20

Abstract

An apparatus to acquire information about light-field data includes: a beam splitter configured to split light, through a lens unit which is connected to the apparatus, from an object into a first light beam and a second light beam; an image sensor configured to detect the first light beam to form an image of the object; and a light-field sensor, including a lenslet array and a detecting unit to detect the second light beam through the lenslet array, configured to acquire information about the light-field data, the lenslet array including a plurality of lenslets, wherein a first position where the detecting unit is provided is conjugate to a second position of a pupil of the lens unit.

Claims

1. An apparatus to acquire information about light-field data comprising:

a beam splitter configured to split light, through a lens unit which is connected to the apparatus, from an object into a first light beam and a second light beam;

an image sensor configured to detect the first light beam to form an image of the object; and

a light-field sensor, including a lenslet array and a detecting unit to detect the second light beam through the lenslet array, configured to acquire information about the light-field data, the lenslet array including a plurality of lenslets,

wherein a first position where the detecting unit is provided is conjugate to a second position of a pupil of the lens unit.

2. The apparatus according to claim 1, further comprising an actuator configured to move the detecting unit in order to maintain a conjugate relationship between the first and the second positions when the pupil of the lens unit is moved according to a zooming operation of the lens unit.

3. The apparatus according to claim 1, wherein the detecting unit comprises a spatial light modulator and a detector to detect the second light beam coming through the lenslet array, and wherein the first position is a position of the spatial light modulator.

4. The apparatus according to claim 3, wherein the spatial light modulator includes pixel groups, each pixel group having a plurality of pixels.

5. The apparatus according to claim 4, wherein each pixel group of the spatial light modulator is associated with each lenslet.

6. The apparatus according to claim 1, wherein the detecting unit comprises an image sensor array.

7. The apparatus according to claim 3, wherein the pupil of the lens unit is formed on the spatial light modulator.

8. The apparatus according to claim 1, wherein powers of the plurality of the lenslets are set according to the pupil of the lens unit.

9. The apparatus according to claim 1, wherein the lenslet array is provided so that an image of the object is formed on the lenslet array.

10. The apparatus according to claim 1, wherein the beam splitter splits the light from the object into visible light to be detected by the image sensor and light, selected from one of visible light, near infrared light, infrared light and ultraviolet light, to be detected by the detecting unit.

11. The apparatus according to claim 10, wherein the second light beam is deflected by the beam splitter and composed of at least one of near infrared light, infrared light, and ultraviolet light.

12. The apparatus according to claim 3, wherein the spatial light modulator and the detector are moved according to a zooming operation of the lens unit.

13. The apparatus according to claim 3, wherein every pixel group of the spatial light modulator is driven.

14. The apparatus according to claim 3, wherein the detector is a photo detector.

15. The apparatus according to claim 3, wherein the spatial light modulator is moved by an actuator according to a zooming operation so that a conjugate relationship between the second position of the pupil of the lens unit and a position of the spatial light modulator is maintained.

16. The apparatus according to claim 4, wherein the image sensor captures the image of the object at a prescribed time frame, and the detecting unit detects the second light beam to obtain a plurality of the light-field data for every pixel group during the prescribed time frame.

17. The apparatus according to claim 16, wherein one light-field data among the plurality of the light-field data is associated with one image data point of the object formed by the image sensor for the prescribed time frame.

18. The apparatus according to claim 2, the detecting unit is moved by the actuator so as to be synchronized with a zooming operation of the lens unit.

19. The apparatus according to claim 2, the actuator is selected from a stepping motor, a micro-electro-mechanical system (MEMS), a voice coil motor, an ultrasonic motor, and a piezoelectric motor.

20. The apparatus according to claim 1, a sampling frequency of the detecting unit is different from a sampling frequency of the image sensor.

22. The apparatus according to claim 2, further comprising a controller to control a movement of the actuator and a memory that stores a look-up table related to shift amounts of the detecting unit to be moved by the actuator when the pupil of the lens unit is moved, wherein, after the lens unit has been connected to the apparatus, the controller receives data of the look-up table stored in the memory to control the actuator to move the detecting unit.

21. The apparatus according to claim 21, the sampling frequency of the detector is higher than the sampling frequency of the image sensor.

23. An apparatus to acquire information about light-field data comprising:

a lens unit;

a beam splitter configured to split light from an object into a first light beam and a second light beam;

an image sensor configured to detect the first light beam to form an image of the object; and

a light-field sensor, including a lenslet array and a detecting unit to detect the second light beam through the lenslet array, configured to acquire information about the light-field data, the lenslet array including a plurality of lenslets,

wherein a first position where the detecting unit is provided is conjugate to a second position of a pupil of the lens unit.

24. A method to acquire information about light-field data comprising:

splitting object light, passing through a lens, unit, into a first light beam and a second light beam;

detecting the first light beam to capture an image of the object;

inputting the second light beam into a lenslet array including a plurality of lenslets;

scanning a spatial light modulator associated with each lenslet of the lenslet array, wherein the spatial light modulator is moved according to a zooming operation of the lens unit so that a conjugate relationship between a position of a pupil of the lens unit and a position of the spatial light modulator is maintained; and

detecting the second light beam coming through the spatial light modulator to acquire information about light-field data of the object.