US 12,326,503 B2
Distance measuring apparatus
Takehiro Hata, Kariya (JP); Noriyuki Ozaki, Kariya (JP); and Teiyu Kimura, Kariya (JP)
Assigned to DENSO CORPORATION, Kariya (JP)
Filed by DENSO CORPORATION, Kariya (JP)
Filed on Dec. 4, 2020, as Appl. No. 17/112,559.
Application 17/112,559 is a continuation of application No. PCT/JP2019/022777, filed on Jun. 7, 2019.
Claims priority of application No. 2018-110325 (JP), filed on Jun. 8, 2018.
Prior Publication US 2021/0088658 A1, Mar. 25, 2021
Int. Cl. G01S 17/08 (2006.01); G01S 7/484 (2006.01); G01S 7/4863 (2020.01); G01S 7/487 (2006.01)
CPC G01S 17/08 (2013.01) [G01S 7/484 (2013.01); G01S 7/4863 (2013.01); G01S 7/4873 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A distance measuring apparatus comprising:
an illuminator which is configured to emit distance-measuring light;
a plurality of photodetectors each of which includes a single-photon avalanche diode operable in a Geiger mode and which work to detect reflected light arising from reflection of the distance-measuring light from an object using the single-photon avalanche diodes;
a time measuring unit which measures time elapsed after emission of the distance-measuring light from the illuminator until a number of the photodetectors which is larger than a given value have detected the reflected light;
a timing controller which is responsive to input of a distance-measuring command from outside to activate the illuminator to emit the distance-measuring light and also to activate the single-photon avalanche diodes constituting the photodetectors in the Geiger mode to execute distance measurement made by the time measuring unit; and
a timing instruction unit which determines a light emission timing at which the timing controller instructs the illuminator to emit the distance-measuring light in response to the distance-measuring command and an activation start timing at which the timing controller activates the single-photon avalanche diodes to operate in the Geiger mode in response to the distance-measuring command, wherein
the timing instruction unit determines the light emission timing and the activation start timing to shorten a period of time for which the number of the photodetectors which have detected the reflected light after emission of the distance-measuring light from the illuminator varies cyclically causing a non-uniform variation in sensitivity of the photodetectors to the reflected light.