Hamamatsu-photonics K.k.

Jun Hiramitsu

Mitsuhito Mase

Akihiro Shimada

Takashi Suzuki

Yuma Tanaka

Toshinori Ito

Hiroaki Ishii

Masaharu Muramatsu

Yasuhito Yoneta

Shin-ichiro Takagi

In a ranging image sensor, each pixel includes an avalanche multiplication region, a charge distribution region, a pair of first charge transfer regions, a pair of second charge transfer regions, a well region, a photogate electrode, a pair of first transfer gate electrodes, and a pair of second transfer gate electrodes. The first multiplication region of the avalanche multiplication region is formed so as to overlap the charge distribution region and so as not to overlap the well region in the Z direction. The second multiplication region of the avalanche multiplication region is formed so as to overlap the charge distribution region and the well region in the Z direction.

Ranging image sensor

A multiplying image sensor includes a semiconductor layer having a first surface and a second surface and a wiring layer provided on the second surface. The semiconductor layer includes a plurality of pixels arranged along the first surface. Each of the plurality of pixels includes a first semiconductor region, a second semiconductor region formed on the second surface side with respect to at least a part of the first semiconductor region and divided for each of the plurality of pixels, and a well region formed in the second semiconductor region so as to be separated from the first semiconductor region and forming a part of a pixel circuit. At least a part of the first semiconductor region and at least a part of the second semiconductor region form an avalanche multiplication region.

Multiplying image sensor

The photosensitive region includes a first impurity region and a second impurity region having a higher impurity concentration than that of the first impurity region. The photosensitive region includes one end positioned away from the transfer section in the second direction and another end positioned closer to the transfer section in the second direction. A shape of the second impurity region in plan view is line-symmetric with respect to a center line of the photosensitive region along the second direction. A width of the second impurity region in the first direction increases in a transfer direction from the one end to the other end. An increase rate of the width of the second impurity region in each of sections, obtained by dividing the photosensitive region into n sections in the second direction, becomes gradually higher in the transfer direction. Here, n is an integer of two or more.

Solid state imaging device

The present embodiment relates to a distance sensor configured to inject an equal amount of current into storage nodes coupled, respectively, to charge collection regions where charges of a photosensitive region is distributed by driving of first and second transfer electrodes and obtain a distance to an object based on difference information on charge amounts of the respective storage nodes. Saturation caused by disturbance light of each storage node is avoided by injecting the equal amount of current to each storage node, and the difference information on the charge amounts of the respective storage nodes, which is not easily affected by the current injection, is obtained by driving the first and second transfer electrodes according to the plurality of frames representing the electrode drive pattern, respectively.

Distance sensor, and method for driving distance sensor

A range sensor includes a silicon substrate and a transfer electrode. The silicon substrate includes a first principal surface and a second principal surface opposing each other. The silicon substrate is provided with a charge generation region configured to generate a charge in response to incident light and a charge collection region configured to collect charges from the charge generation region, on the first principal surface side. The transfer electrode is disposed between the charge generation region and the charge collection region on the first principal surface. A region of the second principal surface corresponding at least to the charge generation region is formed with a plurality of protrusions. The plurality of protrusions includes a slope inclined with respect to a thickness direction of the silicon substrate. A (111) plane of the silicon substrate is exposed as the slope at the protrusion. A height of the protrusion is 200 nm or more.

Distance sensor and distance image sensor

The present embodiment relates to a distance sensor that reduces a difference in amounts of current injected into each of plural charge collection regions prepared for one photosensitive region in order to avoid saturation caused by disturbance light. A current injection circuit injecting current into each charge collection region includes a voltage generation circuit generating a control voltage for adjustment of the injected current amount, and the voltage generation circuit generates the control voltage corresponding to a large amount of charge between the charge amounts of storage nodes coupled, respectively, to the charge collection regions. Meanwhile, a cascode device is disposed between a transistor configured to adjust the amount of current according to the control voltage and the storage node, and a potential of a current output end of the transistor and a potential of the storage node are separated.

Distance sensor

In accordance with an irradiation position of pulsed light, a selecting unit outputs a first transfer signal to a first transfer electrodes and outputs a second transfer signal to a second transfer electrodes, to allow signal charges to flow into first and second signal charge-collecting regions of a pixel corresponding to the irradiation position, and outputs a third transfer signal to a third transfer electrodes to allow unnecessary charges to flow into an unnecessary charge-discharging regions of a pixel other than the pixel corresponding to the irradiation position. An arithmetic unit reads out signals corresponding to respective quantities of signal charges collected in the first and second signal charge-collecting regions of the pixel selected by the selecting unit, and calculates a distance to an object based on a ratio between a quantity of signal charges collected in the first signal charge-collecting regions and a quantity of signal charges collected in the second signal charge-collecting regions.

Distance measuring device

The processing unit causes a light source unit to emit modulated light in one or more emission periods in a plurality of charge transfer cycles within a frame period from connection of an accumulating region to a reset potential to next connection of the accumulating region to the reset potential by controlling a reset switch, and increases the number of emission periods per charge transfer cycle within one frame period. The processing unit obtains, from a sensor unit, a plurality of read values corresponding to a charge amount accumulated in the accumulating region at an alternate point with the plurality of charge transfer cycles, in each of a plurality of read cycles corresponding to each of the plurality of charge transfer cycles. The processing unit calculates the distance based on the plurality of obtained read values.

Distance measurement device

A ranging method uses a light source and a range sensor. The range sensor includes a charge-generating area and first and second charge-accumulating areas. Charges generated in the charge-generating area are transferred to the first charge-accumulating area during a first period so as to be accumulated in the first charge-accumulating area and the second charge-accumulating area during a second period so as to be accumulated in the second charge-accumulating area. A distance d to an object OJ is arithmetized based on a quantity of charges accumulated in the first charge-accumulating area and a quantity of charges accumulated in the second charge-accumulating area. When pulse light is emitted from the light source, the pulse light whose light-intensity stable period within the emission period of the pulse light is set in advance to be longer than each of the first and second periods is emitted from the light source.

Ranging method and ranging device

In a range image sensor, a plurality of range sensors are disposed in a one-dimensional direction. The plurality of range sensors include a photogate electrode, first and second signal charge accumulating regions disposed on one side of the photogate electrode, third and fourth signal charge accumulating regions disposed on the other side, first transfer electrodes for making charge flow into the first and fourth signal charge accumulating regions in response to a first transfer signal, and second transfer electrodes for making charge flow into the second and third signal charge accumulating regions in response to a second transfer signal.

Range image sensor

In a ranging device, a controlling unit alternatively switches orders in time series of a first pulse-transfer-signal and a second pulse-transfer-signal per frame term and outputs the first and second pulse-transfer-signals. Furthermore, an arithmetic unit arithmetizes a distance to an object based on total quantities of charges of signal charges, in two frame term consecutive in the time series, accumulated in a first charge-accumulating region and a second charge-accumulating region in accordance with the first and second pulse-transfer-signals having an identical phase.

Distance-measurement device and method for powering distance-measurement device

In any three of three range sensors consecutively aligned in a one-dimensional direction, first signal charge-accumulating regions are adjacent to each other in the one-dimensional direction in the range sensor positioned in a center of the three range sensors and the range sensor positioned closer to one side of the one-dimensional direction than the range sensor positioned in the center of the three range sensors, and the first signal charge-accumulating region and the second signal charge-accumulating region are adjacent to each other in the one-dimensional direction in the range sensor positioned in the center of the three range sensors and the range sensor positioned closer to an another side of the one-dimensional direction than the range sensor positioned in the center of the three range sensors.

Distance image sensor

A distance sensor includes: a light receiving area including a first longer side and a second longer side; a photo gate electrode arranged on the light receiving area; a plurality of signal charge collection regions along the first longer side; a plurality of signal charge collection regions along the second longer side; a plurality of transfer electrodes along the first longer side provided with charge transfer signals having mutually-differing phases; a plurality of transfer electrodes along the second longer side provided with the charge transfer signals having mutually-differing phases; and a potential adjusting means positioned between the first and second longer sides and raises potential of an area extending in a direction in which the first and second longer sides extend to be higher than potential of side areas of the first and second longer sides.

In a distance measurement device of an embodiment, a light source emits modulation light in a first charge transfer cycle, and emission of the modulation light of the light source is stopped in a second charge transfer cycle. In each of the first and second charge transfer cycles, the charges generated in a photosensitive region are distributed to a first accumulation region and a second accumulation region. A first value is obtained based on readout values corresponding to amounts of accumulated charges of the first accumulation region. A second value is obtained based on readout values corresponding to amounts of accumulated charges of the second accumulation region. A distance is calculated based on the first value and the second value.

A charge generating region is arranged within a region of a polygonal pixel region excluding a corner portion thereof. A signal charge collecting region is arranged at a center portion of the pixel region on the inside of the charge generating region so as to be surrounded by the charge generating region. A photogate electrode is arranged on the charge generating region. A transfer electrode is arranged between the signal charge collecting region and the charge generating region. A semiconductor region has a portion located at the corner portion of the pixel region and the remaining portion located on the outside of the pixel region, and has a conductivity type opposite to that of the signal charge collecting region and an impurity concentration higher than that of surroundings thereof. A readout circuit is arranged in the semiconductor region.

Growing community of inventors

Hamamatsu, Japan

Jun Hiramitsu