DISTANCE MEASUREMENT PROCESSING APPARATUS, DISTANCE MEASUREMENT MODULE, DISTANCE MEASUREMENT PROCESSING METHOD, AND PROGRAM

• US 20190331776A1
• Filed: 04/05/2019
• Published: 10/31/2019
• Est. Priority Date: 04/27/2018
• Status: Active Application

• Current Assignee: Sony Semiconductor Solutions Corporation (Sony Group Corp.)
• Original Assignee: Sony Semiconductor Solutions Corporation (Sony Group Corp.)
• Inventors: Aotake, Shuntaro, Masuno, Tomonori, Kamiya, Takuro
• Application Number:
  US16/375,888
• Publication Number:
  US 20190331776A1
• Time in Patent Office: Days
• CPC Class Codes: G01S 17/10 using transmission of interrupted, pulse-modulated waves determination of distance by phase measurements G01S17/32
• CPC Class Codes: G01S 17/36 with phase comparison between the received signal and the contemporaneously transmitted signal
• CPC Class Codes: G01S 17/894 3D imaging with simultaneous measurement of time-of-flight at a 2D array of receiver pixels, e.g. time-of-flight cameras or flash lidar
• CPC Class Codes: G01S 7/4863 Detector arrays, e.g. charge-transfer gates
• CPC Class Codes: G01S 7/4865 Time delay measurement, e.g. time-of-flight measurement, time of arrival measurement or determining the exact position of a peak peak detection in noise, signal conditioning G01S7/487
• CPC Class Codes: G01S 7/4914 of detector arrays, e.g. charge-transfer gates
• CPC Class Codes: G01S 7/4915 Time delay measurement, e.g. operational details for pixel components signal extraction and conditioning G01S7/493; Phase measurement
• CPC Class Codes: G01S 7/497 Means for monitoring or calibrating

Abstract

There is provided a distance measurement processing apparatus including: a correction parameter calculating section configured to calculate a correction parameter for correcting deviation of characteristics between a first tap and a second tap using a predetermined number of detection signals which are detected two each for two or more types of irradiated light, two or more types of the irradiated light with a predetermined phase difference being radiated on an object, and electric charges generated by reflected light reflected by the object being received being sorted into the first tap and the second tap in accordance with a distance to the object; and a distance measuring section configured to obtain a depth indicating a distance to the object on the basis of the correction parameter and a predetermined number of the detection signals.

Claims

1. A distance measurement processing apparatus comprising:

a correction parameter calculating section configured to calculate a correction parameter for correcting deviation of characteristics between a first tap and a second tap using a predetermined number of detection signals which are detected two each for two or more types of irradiated light, two or more types of the irradiated light with a predetermined phase difference being radiated on an object, and electric charges generated by reflected light reflected by the object being received being sorted into the first tap and the second tap in accordance with a distance to the object; and

a distance measuring section configured to obtain a depth indicating a distance to the object on a basis of the correction parameter and a predetermined number of the detection signals.

2. The distance measurement processing apparatus according to claim 1,

wherein, for a first detection period in which the reflected light of the irradiated light with a first phase is received, and a second detection period in which the reflected light of the irradiated light with a second phase is received, among two types of the irradiated light,

in the first detection period, a plurality of electric charges is alternately sorted into the first tap and the second tap, and a first detection signal in accordance with electric charges sorted and accumulated into the first tap and a second detection signal in accordance with electric charges sorted and accumulated into the second tap are detected, and

in the second detection period, a plurality of electric charges is alternately sorted into the first tap and the second tap, and a third detection signal in accordance with electric charges sorted and accumulated into the first tap and a fourth detection signal in accordance with electric charges sorted and accumulated into the second tap are detected.

3. The distance measurement processing apparatus according to claim 2,

wherein the correction parameter calculating section calculates two types of the correction parameter using the first detection signal, the second detection signal, the third detection signal and the fourth detection signal.

4. The distance measurement processing apparatus according to claim 3,

wherein the correction parameter calculating section includes

a calculating section configured to calculate two types of the correction parameter, and

a storage section configured to store one type of the correction parameter calculated by the calculating section.

5. The distance measurement processing apparatus according to claim 4,

wherein the calculating section calculates one type of the correction parameter to be stored in the storage section upon start of processing of obtaining the depth by the distance measuring section and stores the one type of the correction parameter in the storage section.

6. The distance measurement processing apparatus according to claim 5,

wherein the storage section holds the correction parameter for each pixel of a light receiving section which receives the reflected light.

7. The distance measurement processing apparatus according to claim 5,

wherein the calculating section obtains an offset parameter for correcting deviation of characteristics between the first tap and the second tap with an offset as the one type of the correction parameter to be stored in the storage section.

8. The distance measurement processing apparatus according to claim 7,

wherein the calculating section obtains the offset parameter using,

in addition to the first detection signal, the second detection signal, the third detection signal and the fourth detection signal,

a fifth detection signal in accordance with electric charges sorted and accumulated into the first tap and a sixth detection signal sorted and accumulated into the second tap, among a plurality of electric charges which is alternately sorted into the first tap and the second tap in a third detection period in which the reflected light of the irradiated light with a third phase is received, and

a seventh detection signal in accordance with electric charges sorted and accumulated into the first tap and an eighth detection signal sorted and accumulated into the second tap, among a plurality of electric charges which is alternately sorted into the first tap and the second tap in a fourth detection period in which the reflected light of the irradiated light with a fourth phase is received.

9. The distance measurement processing apparatus according to claim 5,

wherein the calculating section obtains a gain parameter for correcting deviation of characteristics between the first tap and the second tap with a gain as the other type of the correction parameter.

10. The distance measurement processing apparatus according to claim 9,

wherein the calculating section obtains the gain parameter for each one frame of the depth output at a predetermined frame rate.

11. The distance measurement processing apparatus according to claim 2,

wherein the distance measuring section includes

a correction operating section configured to perform operation of obtaining a first corrected detection signal by correcting the first detection signal and obtaining a second corrected detection signal by correcting the third detection signal, or operation of obtaining a third corrected detection signal by correcting the second detection signal and obtaining a fourth corrected detection signal by correcting the fourth detection signal, using the correction parameter calculated by the correction parameter calculating section, and

a distance measurement operating section configured to perform operation of obtaining the depth using the first detection signal, the third detection signal, the third corrected detection signal and the fourth corrected detection signal, or operation of obtaining the depth using the second detection signal, the fourth detection signal, the first corrected detection signal and the second corrected detection signal.

12. The distance measurement processing apparatus according to claim 1, further comprising:

a distance measurement result storage section configured to store the depth obtained by the distance measuring section; and

a result synthesizing section configured to synthesize the depth of a frame one frame before a current frame stored in the distance measurement result storage section and the depth of the current frame and output the synthesized depth.

13. The distance measurement processing apparatus according to claim 12,

wherein the distance measuring section obtains reliability for the depth along with the depth,

the reliability is stored along with the depth in the distance measurement result storage section, and

the result synthesizing section synthesizes the depth of the frame one frame before the current frame and the depth of the current frame by performing weighted addition in accordance with the reliability.

14. A distance measurement module comprising:

a light emitting section configured to radiate two types of irradiated light with a predetermined phase difference to an object;

a light receiving section configured to output a predetermined number of detection signals which are detected two each for two types of the irradiated light, electric charges generated by reflected light reflected by the object being received being sorted into a first tap and a second tap in accordance with a distance to the object;

a correction parameter calculating section configured to calculate a correction parameter for correcting deviation of characteristics between the first tap and the second tap using a predetermined number of the detection signals; and

a distance measuring section configured to obtain a depth indicating a distance to the object on a basis of the correction parameter and a predetermined number of the detection signals.

15. A distance measurement processing method to be performed by a distance measurement processing apparatus which performs distance measurement processing, the distance measurement processing method comprising:

calculating a correction parameter for correcting deviation of characteristics between a first tap and a second tap using a predetermined number of detection signals which are detected two each for two types of irradiated light, two types of the irradiated light with a predetermined phase difference being radiated on an object, and electric charges generated by reflected light reflected by the object being received being sorted into the first tap and the second tap in accordance with a distance to the object; and

obtaining a depth indicating a distance to the object on a basis of the correction parameter and a predetermined number of the detection signals.

16. A program for causing a computer of a distance measurement processing apparatus which performs distance measurement processing to execute distance measurement processing comprising:

calculating a correction parameter for correcting deviation of characteristics between a first tap and a second tap using a predetermined number of detection signals which are detected two each for two types of irradiated light, two types of the irradiated light with a predetermined phase difference being radiated on an object, and electric charges generated by reflected light reflected by the object being received being sorted into the first tap and the second tap in accordance with a distance to the object; and

obtaining a depth indicating a distance to the object on a basis of the correction parameter and a predetermined number of the detection signals.