US-12618973-B2 - Distance measuring device and distance measuring method

Abstract

The present disclosure relates to a distance measuring device and a distance measuring method enabling use of a plurality of sensors employing different distance measurement schemes in combination at low cost. A pixel region including a pixel including a SPAD to be used for distance measurement using a direct ToF scheme and a pixel including a current assisted photonic demodulator (CAPD) to be used for distance measurement using an indirect ToF scheme or a normal pixel, and a light emitting unit are shared and controlled. The present disclosure can be applied to a distance measuring device.

Inventors

• KUMIKO MAHARA

Assignees

• SONY SEMICONDUCTOR SOLUTIONS CORPORATION

Dates

Publication Date

20260505

Application Date

20210325

Priority Date

20200408

Claims (19)

1. 1 . A distance measuring device, comprising: a light emitting unit configured to emit distance measurement light; a pixel region including a first pixel to be used for distance measurement based on a first time of flight (ToF) scheme and a second pixel to be used for distance measurement based on a second ToF scheme; and a control unit configured to control the first pixel, the second pixel, and the light emitting unit, wherein the first ToF scheme is a direct ToF scheme, and the first pixel includes an avalanche diode, and the second ToF scheme is an indirect ToF scheme, and the second pixel includes a current assisted photonic demodulator (CAPD) or a normal pixel.
2. 2 . The distance measuring device according to claim 1 , wherein the control unit is further configured to: cause the light to be emitted so as to repeat light emission and extinction at a specific frequency in a case where the first pixel is exposed, and control the light emission so that the light emission and extinction are repeated at a frequency higher than the specific frequency in a case where the second pixel is exposed.
3. 3 . The distance measuring device according to claim 1 , wherein the control unit is further configured to: cause the light emitting unit to emit light with first light emission intensity in a case where the first pixel is exposed, and cause the light emitting unit to emit light with second light emission intensity lower than the first light emission intensity in a case where the second pixel is exposed.
4. 4 . The distance measuring device according to claim 1 , wherein the control unit is further configured to cause the light emitting unit to emit spot light in a case where the first pixel is exposed, and cause the light emitting unit to emit the light over an entire surface in a case where the second pixel is exposed.
5. 5 . The distance measuring device according to claim 1 , wherein the control unit is further configured to cause the light emitting unit to emit the light only in a region where an object exists in a case where the first pixel is exposed, and cause the light emitting unit to emit the light over an entire surface in a case where the second pixel is exposed.
6. 6 . The distance measuring device according to claim 1 , wherein the control unit is further configured to cause each of the first pixel and the second pixel to be exposed in a time division manner.
7. 7 . The distance measuring device according to claim 6 , wherein the control unit is further configured to cause each of the first pixel and the second pixel to be alternately exposed at a specific interval.
8. 8 . The distance measuring device according to claim 6 , wherein the control unit is further configured to cause each of the first pixel and the second pixel to be exposed in a specific order.
9. 9 . The distance measuring device according to claim 6 , wherein the control unit is further configured to switch exposure between the first pixel and the second pixel in a case where a specific condition is satisfied.
10. 10 . The distance measuring device according to claim 9 , wherein the control unit is further configured to start exposure of the first pixel and switches exposure to exposure of the second pixel based on a distance measurement result of the first pixel.
11. 11 . The distance measuring device according to claim 1 , wherein the pixel region includes a region where a plurality of first pixels are arranged in a concentrated manner and a region where a plurality of second pixels are arranged in a concentrated manner, the plurality of first pixels include the first pixel, and the plurality of second pixels include the second pixel.
12. 12 . The distance measuring device according to claim 1 , wherein in the pixel region, a plurality of first pixels are arranged in a line, and a plurality of second pixels are arranged in a line, the plurality of first pixels include the first pixel, and the plurality of second pixels include the second pixel.
13. 13 . The distance measuring device according to claim 1 , wherein in the pixel region, a line in which a plurality of first pixels are arranged and a line in which a plurality of second pixels are arranged are alternately arranged, the plurality of first pixels include the first pixel, and the plurality of second pixels include the second pixel.
14. 14 . The distance measuring device according to claim 1 , wherein in the pixel region, a specific number of lines in which a plurality of first pixels are arranged and a specific number of lines in which a plurality of second pixels are arranged are alternately arranged, the plurality of first pixels include the first pixel, and the plurality of second pixels include the second pixel.
15. 15 . The distance measuring device according to claim 1 , wherein in the pixel region, lines in which a plurality of first pixels are arranged and lines in which a plurality of second pixels are arranged are alternately arranged such that a number of lines in which the plurality of first pixels are arranged is different from a number of lines in which the plurality of second pixels are arranged, the plurality of first pixels include the first pixel, and the plurality of second pixels include the second pixel.
16. 16 . The distance measuring device according to claim 1 , wherein in the pixel region, a size of the first pixel is different from a size of the second pixel.
17. 17 . The distance measuring device according to claim 1 , further comprising: a depth map generation unit configured to generate a depth map based on a a distance measurement result by the first pixel and a distance measurement result by the second pixel.
18. 18 . The distance measuring device according to claim 17 , further comprising: an unnecessary region determination unit configured to determine an unnecessary region in a distance measurement region by the first pixel and the second pixel based on the depth map.
19. 19 . A distance measuring method, comprising: in a distance measuring device including: a light emitting unit configured to emit distance measurement light; a pixel region including a first pixel to be used for distance measurement based on a first time of flight (ToF) scheme and a second pixel to be used for distance measurement based on a second ToF scheme; and a control unit configured to control the first pixel, the second pixel, and the light emitting unit, the distance measuring method comprising: controlling, by the control unit, the first pixel, the second pixel, and the light emitting unit, wherein the first ToF scheme is a direct ToF scheme, and the first pixel includes an avalanche diode, and the second ToF scheme is an indirect ToF scheme, and the second pixel includes a current assisted photonic demodulator (CAPD) or a normal pixel.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application is a U.S. National Phase of International Patent Application No. PCT/JP2021/012468 filed on Mar. 25, 2021, which claims priority benefit of Japanese Patent Application No. JP 2020-069486 filed in the Japan Patent Office on Apr. 8, 2020. Each of the above-referenced applications is hereby incorporated herein by reference in its entirety. TECHNICAL FIELD The present disclosure relates to a distance measuring device and a distance measuring method, and more particularly to a distance measuring device and a distance measuring method that enabled use of a plurality of sensors employing different distance measurement schemes in combination at low cost. BACKGROUND ART In recent years, as a distance measurement scheme that has attracted attention, a distance measuring sensor that measures a distance using a Time-of-Flight (ToF) method has attracted attention. Distance measuring sensors include a sensor employing a direct ToF scheme capable of measuring a long distance and a sensor employing an indirect ToF scheme capable of measuring a relatively short distance with high accuracy. For example, Patent Document 1 discloses a distance measuring sensor employing the direct ToF scheme. In addition, Patent Document 2 discloses a distance measuring sensor employing the indirect ToF scheme. CITATION LIST Patent Document Patent Document 1: International Publication No. 2018/074530Patent Document 2: Japanese Patent Application Laid-Open No. 2011-86904 SUMMARY OF THE INVENTION Problems to be Solved by the Invention By the way, in a configuration of a distance measuring device, use of a plurality of distance measuring sensors employing different distance measurement schemes makes it possible to cover a wide distance measurement range. However, if a distance measuring sensor employing a direct ToF scheme and a distance measuring sensor employing an indirect ToF scheme are simply combined, a device scale increases and cost increases. The present disclosure has been made in view of such a situation and is particularly directed to enabling use of a plurality of sensors employing different distance measurement schemes in combination at low cost. Solutions to Problems A distance measuring device according to one aspect of the present disclosure is a distance measuring device including: a light emitting unit configured to emit distance measurement light; a pixel region including a first pixel to be used for distance measurement using a first time of flight (ToF) scheme and a second pixel to be used for distance measurement using a second ToF scheme; and a control unit configured to control the first pixel, the second pixel, and the light emitting unit. A distance measuring method according to one aspect of the present disclosure is a distance measuring method of a distance measuring device including: a light emitting unit configured to emit distance measurement light; a pixel region including a first pixel to be used for distance measurement using a first time of flight (ToF) scheme and a second pixel to be used for distance measurement using a second ToF scheme; and a control unit configured to control the first pixel, the second pixel, and the light emitting unit, the distance measuring method including a step of the control unit controlling the first pixel, the second pixel, and the light emitting unit. In one aspect of the present disclosure, a light emitting unit configured to emit distance measurement light, a first pixel and a second pixel in a pixel region including the first pixel to be used for distance measurement using a first time of flight (ToF) scheme, and the second pixel to be used for distance measurement using a second ToF scheme are controlled. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a view illustrating an example of a detection range in a case where a distance measuring device is mounted on a vehicle. FIG. 2 is a view for explaining a configuration example of a distance measuring device including an iToF sensor and a dToF sensor. FIG. 3 is a view for explaining another configuration example of the distance measuring device including the iToF sensor and the dToF sensor. FIG. 4 is a view for explaining control of the distance measuring device including the iToF sensor and the dToF sensor. FIG. 5 is a view for explaining outline of a distance measuring device of the present disclosure. FIG. 6 is a view for explaining a configuration example of a first embodiment of the distance measuring device of the present disclosure. FIG. 7 is a view for explaining a distance measuring method using a dTOF sensor. FIG. 8 is a view for explaining a distance measuring method using an iTOF sensor. FIG. 9 is a view illustrating a first configuration example of a pixel in a dTOF pixel region. FIG. 10 is a view illustrating a second configuration example of the pixel in the dTOF pixel region. FIG. 11 is a view illustrating a third configuration example of the pixel in the dTOF pi