Image capturing apparatus and storage medium for storing image capturing control program

Patent metadata

Field	Value
Publication number	US-9888189-B2
Application number	US-201615091334-A
Country	US
Kind code	B2
Filing date	Apr 5, 2016
Priority date	Apr 6, 2015
Publication date	Feb 6, 2018
Grant date	Feb 6, 2018

Abstract

An image capturing apparatus includes a light emission controller configured to make a light emitter provide a first light emission and a second light emission with a light emission amount calculated based on a result of photometry in the first light emission, the light emitter being configured to emit illumination light of the object field, and a switch configured to switch a readout of an exposure control signal between first and second signal readouts to obtain a result of the photometry in the first light emission. In the first signal readout signals from a plurality of photoelectric conversion elements are synthesized and read out. In the second signal readout, an output of a first photoelectric conversion element is read out among a plurality of photoelectric conversion elements in an image sensor and then an output of a second photoelectric conversion element is read out.

First claim

What is claimed is:

1. An image capturing apparatus comprising:
an image captures having a plurality of pixels each including a plurality of photoelectric conversion elements for each micro lens;
a reader configured to read a signal from the pixel by a first signal readout in which signals from the plurality of photoelectric conversion elements are synthesized and read out and a second signal readout in which an output of a first photoelectric conversion element is read out among the plurality of photoelectric conversion elements and then an output of a second photoelectric conversion element is read out;
a photometer configured to provide photometry using a signal read out of at least a part of pixel area that has received light from an object field;
a light emission controller configured to make a light emitter provide a first light emission and a second light emission with a light emission amount calculated based on a result of the photometry in the first light emission, the light emitter being configured to emit light to illuminate the object field; and
a switcher configured to switch a readout of an exposure control signal from the pixel area, between the first signal readout and the second signal readout;
wherein the switcher switches the readout of the exposure control signal between the first signal readout and the second signal readout based on the result of the photometry in a non-light emission of the light emitter before the first light emission.

2. The image capturing apparatus according to claim 1 , wherein the switcher switches the readout of the exposure control signal between the first signal readout and the second signal readout for each of the plurality of pixel areas.

3. The image capturing apparatus according to claim 1 , wherein the switcher sets the readout of the exposure control signal to the first signal readout when a luminance of the object field as the result of the photometry in the non-light emission of the light emitter before the first light emission is higher than a predetermined luminance, and to the second signal readout when the luminanceof the object field is equal to or lower than the predetermined luminance.

4. The image capturing apparatus according to claim 1 , further comprising:
an exposure controller configure to calculate an exposure time period of the image capturer in the first light emission as the result of the photometry in the non-light emission time of the light emitter,
wherein the switcher sets the readout of the exposure control signal to the first signal readout when the exposure time period is longer than a predetermined time period, and to the second signal readout when the exposure time period is equal to or shorter than the predetermined time period.

5. The image capturing apparatus according to claim 1 , further comprising:
a focus information acquirer configured to acquire information relating to a focusing state in the plurality of image areas based on a first image generated with a signal read out of the first photoelectric conversion element and a second image signal generated with a signal read out of the second photoelectric conversion element,
wherein the focus information acquirer acquires the information relating to the focusing state using the first and second signals read by the second signal readout, when the switcher sets the readout of the exposure control signal to the second signal readout.

6. A non-transitory computer readable storage medium configured to store a computer program for a computer in an image capturing apparatus that includes an image capturer having a plurality of pixels each including a plurality of photoelectric conversion elements for each micro lens, and reads a signal from the pixel by a first signal readout in which signals from the pluralityof photoelectric conversion elements are synthesized and read out, and a second signal readout in which an output of a first photoelectric conversion element is read out among the plurality of photoelectric conversion elements and then an output of a second photoelectric conversion element is read out, the computer program enabling the computter to execute processing of;
providing photometry using a signal read out of at least a part of pixel area that has received light from an object field;
making a light emitter provide a first light emission and a second light emission with a light emission amount calculated based on a result of the photometry in the first light emission, the light emitter being configured to emit illumination light of the object field; and
switching a readout of an exposure control signal from the pixel area, between the first signal readout and the second signal readout;
wherein the switcher switches the readout of the exposure control signal between the first signal readout and the second signal readout based on the result of the photometry in a non-light emission of the light emitter before the first light emission.

Assignees

• Canon Kk

Inventors

• Kageyama Takashi

Classifications

• H04N25/134 Primary

  based on three different wavelength filter elements · CPC title

• H04N25/704

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

• H04N23/71

  Circuitry for evaluating the brightness variation · CPC title

• H04N25/778

  comprising amplifiers shared between a plurality of pixels, i.e. at least one part of the amplifier must be on the sensor array itself · CPC title

• H04N23/73

  by influencing the exposure time · CPC title