Distance measuring device

Patent metadata

Field	Value
Publication number	US-10101452-B2
Application number	US-201715434550-A
Country	US
Kind code	B2
Filing date	Feb 16, 2017
Priority date	Mar 24, 2016
Publication date	Oct 16, 2018
Grant date	Oct 16, 2018

Abstract

In a distance measuring device, a pixel G includes sub pixels Po and Pe in a row direction. Floating diffusion parts Fd1 to Fd4 detect charge quantities relating to reflected modulated light Lb in four terms which are delayed in start by every ¼ of a period of emitted modulated light La in order. A binning group Gv is configured by an array part that the two sub pixels Po and the two sub pixels Pe are adjacent to each other in a row direction.

First claim

What is claimed is:

1. A distance measuring device comprising:
an imaging element which includes a plurality of pixels of a grid array and makes a stored charge quantity of charges which have been generated in relation to an intensity of incident light readable from the outside in units of pixels;
a modulated light emission unit which emits modulated light the intensity of which has been modulated toward an imaging range of the imaging element;
a phase difference detection unit which detects a phase difference between emitted modulated light that the modulated light emission unit has emitted and reflected modulated light which has been obtained as a result of incidence of the emitted modulated light which has been reflected from an object for distance measurement within the imaging range upon the pixels of the imaging element on the basis of the stored charge quantity which has been read out of the imaging element in units of the pixels; and
a distance measuring unit which measures a distance from the distance measuring device to the object for distance measurement on the basis of the phase difference that the phase difference detection unit has detected, wherein
each pixel includes a first sub pixel and a second sub pixel which have been arrayed adjacently to each other in a row direction,
a first term, a second term, a third term and a fourth term which have equal lengths which are less than one period of the emitted modulated light and are delayed in start by every ¼ of the period of the emitted modulated light in order are set,
the first sub pixel includes a first charge generation part which generates the charges of the charge quantity which is related to the intensity of incident light, a first charge storage part which stores the charges that the first charge generation part has generated in the first term, and a third charge storage part which stores the charges that the first charge generation part has generated in the third term,
the second sub pixel includes a second charge generation part which generates the charges of the charge quantity which is related to the intensity of incident light, a second charge storage part which stores the charges that the second charge generation part has generated in the second term, and a fourth charge storage part which stores the charges that the second charge generation part has generated in the fourth term,
the phase difference detection unit reads the stored charge quantity of the first charge storage part, the stored charge quantity of the second charge storage part, the stored charge quantity of the third charge storage part and the stored charge quantity of the fourth charge storage part as the stored charge quantities out of the imaging element and detects the phase difference on the basis of the read-out stored charge quantities,
a first row part that the two first sub pixels are continuously arrayed in the row direction and a second row part that the two second sub pixels are continuously arrayed in the row direction are alternately arrayed in the row direction in each row of the grid array,
in the adjacent first sub pixels in each first row part, the mutual first charge storage parts are connected together by a first connection wire which allows switching between a connected state and an unconnected state, and the mutual third charge storage parts are connected together by a third connection wire which allows switching between the connected state and the unconnected state, and
in the adjacent second sub pixels in the second row part, the mutual second charge storage parts are connected together by a second connection wire which allows switching between the connected state and the unconnected state, and the mutual fourth charge storage parts are connected together by a fourth connection wire which allows switching between the connected state and the unconnected state.

2. The distance measuring device according to claim 1 , wherein
the grid array includes a column of only the first sub pixels and a column of only the second sub pixels,
an assembly of the sub pixels in which two groups in each of which one first row part and one second row part are adjacent to each other in the row direction are continuously arranged in a column direction is set as one sub pixel group, and
in each sub pixel group, the mutual first connection wires are connected together by a fifth connection wire which allows switching between the connected state and the unconnected state, the mutual second connection wires are connected together by a sixth connection wire which allows switching between the connected state and the unconnected state, the mutual third connection wires are connected together by a seventh connection wire which allows switching between the connected state and the unconnected state, and the mutual fourth connection wires are connected together by an eighth connection wire which allows switching between the connected state and the unconnected state.

3. The distance measuring device according to claim 2 , wherein
each sub pixel is partitioned into a first region in which the first charge generation part or the second charge generation part is arranged and a second region in which either the first charge storage part and the third charge storage part or the second charge storage part and the fourth charge storage part are arranged in the column direction, and
in each sub pixel group, the mutually corresponding sub pixels which are adjacent to each other in the column direction are arranged with the mutual second regions thereof being adjacent to each other in the column direction.

Assignees

• Stanley Electric Co Ltd

Inventors

• Ikeno Ryohei
• Goto Hiroshige

Classifications

• H04N25/704 Primary

  Pixels specially adapted for focusing, e.g. phase difference pixel sets · CPC title

• H04N25/46

  by combining or binning pixels · CPC title

• G01S7/4863 Primary

  Detector arrays, e.g. charge-transfer gates · CPC title

• H04N25/42

  by switching between different modes of operation using different resolutions or aspect ratios, e.g. switching between interlaced and non-interlaced mode · CPC title

• G01S17/894

  Three-dimensional [3D] imaging with simultaneous measurement of time-of-flight at a two-dimensional [2D] array of receiver pixels, e.g. time-of-flight cameras or flash lidar · CPC title