Denso Corporation

Teiyu Kimura

Noriyuki Ozaki

Shinji Kashiwada

Kenta Azuma

Isamu Takai

Takehiro Hata

Hiroyuki Matsubara

Shigeyoshi Hiratsuka

Mitsuhiro Kiyono

Mitsuhiko Ohta

Kenichi Yanai

Yoshihide Tachino

Mineki Soga

A light ranging apparatus is provided with a light source; a light receiving unit having a plurality of light receiving elements capable of outputting a pulse signal; a summing unit calculating a sum value by summing the number of pulses; a histogram generation unit generating a histogram that records the sum value; a peak detecting unit acquiring the sum value of the peak in the histogram to be a signal intensity and calculating a distance value; and a first low signal intensity detecting unit detecting a low signal intensity lower than a predetermined first threshold. The histogram generation unit repeatedly acquires and accumulates the sum value for the histogram where the low signal intensity is detected until the signal intensity becomes the first threshold or more, thereby updating the histogram; and the peak detecting unit calculates a new distance value from the updated histogram.

Light ranging apparatus

An optical distance measuring apparatus comprises a laser diode emitting a light pulse, light receiver including a photon-counting light receiver, distance measurement unit including a signal discriminator and propagation estimator, and threshold determiner. The signal discriminator discriminates the signal component, exceeding a threshold, of the signal as a reflected signal resulting from reflection of the light pulse at a measurement object. The propagation estimator estimates a round-trip propagation time of the light pulse to the measurement object using the signal. The threshold determiner sets a boundary level as the threshold, corresponding to a reference level obtained from the signal when the signal discriminator determines the reflected signal, using the relationship between the reference and the boundary level. The reference level is obtained from the average value of a noise probability distribution in the signal. The boundary level represents a predetermined cumulative probability in the noise probability distribution.

Optical distance measuring apparatus

An optical distance measuring device includes: a light source unit that irradiates a measurement region with irradiation light; a light receiving unit that has a light receiving surface including a plurality of light receiving elements capable of receiving reflected light from a range including the measurement region corresponding to irradiation with the irradiation light and outputs a signal corresponding to a light receiving state of the reflected light for each of the light receiving elements; and a measurement unit that measures a distance to an object in the measurement region by using the signal outputted from the light receiving unit. The light receiving unit has a function of selecting a light receiving element that outputs the signal so that a light receiving position at which the reflected light is received is variable, and the light receiving unit changes the light receiving position to a plurality of positions with respect to a position of the reflected light.

Optical distance measuring device

A distance measuring apparatus is provided which includes an illuminator, a plurality of photodetectors which detect reflected light arising from reflection of light, as emitted from the illuminator, from an object using SPADs, a time measuring unit which measures time elapsed after the emission of light from the illuminator until a number of the photodetectors which is larger than a given value have detected light, a timing controller which instructs the illuminator to emit the light, activates the SPADs in a Geiger mode, and instructs the time measuring unit to execute the time measurement, and a timing instruction unit which determines a light emission timing and an activation start timing of each of the SPADs for the timing controller.

Distance measuring apparatus

An optical ranging device includes a light emitting section provided with a semiconductor laser element having a light emitting region whose length in a first direction is more than that in a second direction intersecting the first direction. The device measures the distance to an object based on the time from light emission from the light emitting section to reception of the light by a light receiving section. A plurality of light emitting regions may be provided in the light emitting section such that they are separated in the second direction and abut or partially overlap each other in the first direction so that the light emitting regions are continuous in the first direction.

Optical ranging device, laser light emitting device, and method for manufacturing the same

An optical distance measuring device includes: a light source unit; a light receiving unit that includes a plurality of light receiving elements; an addition unit that adds the number of pulse signals; a histogram generation unit that generates a histogram that records the addition value for each time of flight; a peak detection unit that determines a distance value from the time of flight corresponding to the peak; an image generation unit that generates signal intensity image data and distance image data; a low signal intensity element detection unit that detects a low signal intensity element from the elements of the signal intensity image data; and an image correction unit that corrects a distance value recorded in a target element corresponding to the low signal intensity element in accordance with a distance value of at least one other element in the elements of the distance image data.

A light reception array unit receives light irradiated from an irradiation unit and reflected from an object, and outputs in parallel a pulse signal respectively output from a plurality of light reception units. A timer unit measures an elapsed time since an input of an irradiation timing signal. A response acquisition unit acquires a number of responses, which is a number of the light reception units outputting the pulse signal, at each fixed cycle timing, and outputs an adjusted number of responses obtained by subtracting a bias value from the number of responses or dividing the number of responses by the bias value. An address of a memory is associated with a timer value measured by the timer unit. A histogram generation unit integrates and stores, in a memory address specified from a timer value, the adjusted number of responses as data at that address.

Photodetector

A plurality of photodetectors form a light receiving group, and a plurality of the light receiving groups form one pixel. A light receiving array is provided with one or more of such pixels. The photodetectors each output a pulse signal in response to irradiation of a photon. A measuring unit is provided for each of the plurality of light receiving groups. The measuring unit generates time information representing an elapsed time from an irradiation timing input from outside and light quantity information acquired at each of one or more timings identified from the time information, in accordance with the pulse signal output from the light receiving group. The number of the photodetectors outputting the pulse signal among the plurality of photodetectors belonging to the light receiving group is used as the light quantity information.

Optical measuring device comprising a measuring unit to generate time information representing an elapsed time in accordance with pulse signal output from a light receiving group

A light detector is provided to include a light receiving array having a plurality of light receivers respectively outputting pulse signals upon incidence of photons. A delay setting value is set which is used to adjust a time interval from when the pulse signals are output from the light receiving array to when a response number, which is a specified number of the light receivers outputting the pulse signals, is acquired.

Light detector comprising a time interval adjusting performance by a delay setting module

A photodetector includes plural detectors. Each of the plural detectors has a single photon avalanche diode (hereinafter referred to as SPAD) which responds to incidence of a photon. The plural detectors include at least a first detector and a second detector. The SPAD has a recovery time period until the SPAD reaches a next photon-responsive state, in response to the SPAD responding to the incidence of the photon. The recovery time period of the SPAD in the first detector is different from the recovery time period of the SPAD in the second detector.

Photodetector and distance measurement apparatus comprising plural single photon avalanche diodes with different recovery time periods

A photodetector includes: a photoreceptor provided with a SPAD that is configured to respond to incidence of a photon, and as the response of the SPAD, configured to output a pulse signal; and a pulse rate control circuit configured to control sensitivity of the photoreceptor to have a pulse rate as the number of pulse signals outputted per unit time from the photoreceptor to be a set value set in advance, (i) in a set range including the set value, (ii) in a set range of the set value or more, or (iii) in a set range of the set value or less.

A light detector is provided to include a detection module, and a monitoring SPAD. The detection module includes an SPAD that is an avalanche photodiode operable in Geiger mode; the detection module is configured to perform light detection by applying, to the SPAD, a reverse bias voltage in a reverse direction. The monitoring SPAD has characteristics identical to characteristics of the SPAD in the detection module. The reverse bias voltage is generated to be applied to the SPAD in the detection module based on (i) a reference breakdown voltage set from a breakdown voltage generated across the monitoring SPAD in Geiger mode and (ii) a predetermined excess voltage.

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Kariya, Japan

Teiyu Kimura