LIGHT-EMITTING APPARATUS FOR SHOOTING WITH FLASH, CHARGING CONTROL METHOD THEREFOR, AND STORAGE MEDIUM

• US 20190313004A1
• Filed: 03/29/2019
• Published: 10/10/2019
• Est. Priority Date: 04/04/2018
• Status: Abandoned Application

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Matsumoto, Yukihiro, Takai, Junji
• Application Number:
  US16/369,486
• Publication Number:
  US 20190313004A1
• Time in Patent Office: Days
• CPC Class Codes: G03B 15/05 Combinations of cameras with electronic flash apparatus; Electronic flash units
• CPC Class Codes: G03B 2215/0567 Solid-state light source, e.g. LED, laser
• CPC Class Codes: H02J 7/007 Regulation of charging or discharging current or voltage
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices
• CPC Class Codes: H04N 23/71 Circuitry for evaluating the brightness variation
• CPC Class Codes: H04N 23/74 by influencing the scene brightness using illuminating means
• CPC Class Codes: H05B 41/325 by measuring the incident light
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light

Abstract

A light-emitting apparatus which capable of preventing the perfect moment to take a photograph from being missed while reducing draining of a charging unit caused by charging thereof. In accordance with an instruction from a camera 100, a flash MPU of an external flash 120 switches to perform one of a first charging control and a second charging control in accordance with a first instruction from the camera 100. The first charging control charges the charging unit 202 until a charging voltage thereof reaches a target first level and then maintains the charging level at the first level, and the second charging control charges said charging unit 202 until the charging voltage reaches the first level when the charging voltage reaches a second level lower than the first level.

Claims

1. A light-emitting apparatus comprising:

a light-emitter;

a charging unit configured to have a capacitor and to be charged with electrical charge for causing said light-emitter to emit light; and

at least one processor and at least one memory functioning as;

a switching unit configured to switch to perform one of a first charging control and a second charging control, wherein in the first charging control charges said charging unit until a charging voltage of said charging unit reaches a target first level and then maintains the charging level at the first level, and the second charging control charges said charging unit until the charging voltage reaches the first level when the charging voltage reaches a second level lower than the first level.

2. The light-emitting apparatus according to claim 1, wherein the light-emitting apparatus is at least one of a light-emitting apparatus that is mounted on an image pickup apparatus and a light-emitting apparatus that is integral with the image pickup apparatus.

3. The light-emitting apparatus according to claim 1, wherein the first level is a level at which maximum light emission by said light-emitter is possible, and the second level is a level at which light emission by said light-emitter is ensured.

4. The light-emitting apparatus according to claim 2, wherein in a case where the image pickup apparatus is in a shooting instruction waiting state, an instruction to perform the second charging control is issued, and in a case where a user has operated a shooting preparation switch in the shooting instruction waiting state, and the image pickup apparatus has started preparing for taking a photograph, an instruction to perform the first charging control is issued.

5. The light-emitting apparatus according to claim 2, wherein the processor functioning as:

a setting unit configured to set one of a plurality of light emission modes; and

a notification unit configured to notify the image pickup apparatus of the light emission mode set by said setting unit,

wherein in a case where the image pickup apparatus is in a shooting instruction waiting state, one of an instruction to perform the first charging control and an instruction to perform the second charging control is issued according to the light emission mode of which the image pickup apparatus has been notified by said notification unit.

6. The light-emitting apparatus according to claim 5, wherein the plurality of light emission modes includes a first light emission mode in which light emission and non-light emission are switched when a photograph is taken according to a result of photometry by the image pickup apparatus, and a second light emission mode in which a light emission is performed when a photograph is taken,

when the light emission mode of which the image pickup apparatus has been notified is the first light emission mode, said switching unit switches to perform one of the first charging control and the second charging control in accordance with the instruction from the image pickup apparatus, and

when the light emission mode of which the image pickup apparatus has been notified is the second light emission mode, said switching unit switches to perform the first charging control.

7. The light-emitting apparatus according to claim 2, wherein in a case where the image pickup apparatus has been shifted into a power saving mode, the image pickup apparatus issues a second instruction to perform the third charging control, and in accordance with the second instruction, said switching unit switches to perform a third charging control that charges said charging unit until the charging voltage reaches a third level between the first level and the second level, when the charging voltage has reached the second level.

8. The light-emitting apparatus according to claim 7, wherein the processor functioning as:

a stop unit configured to stop charging said charging unit after the third charging control is started, when the number of times said charging unit has been recharged becomes equal to or greater than a predetermined number of times.

9. A charging control method for a light-emitting apparatus comprising a light-emitter, and a charging unit that has a capacitor and is charged with electrical charge for causing the light-emitter to emit light, comprising:

switching to perform one of a first charging control and a second charging control, wherein the first charging control charges the charging unit until a charging voltage of the charging unit reaches a target first level and then maintains the charging level at the first level, and the second charging control charges the charging unit until the charging voltage reaches the first level when the charging voltage reaches a second level lower than the first level.

10. A non-transitory computer-readable storage medium storing a program for causing a computer to execute a charging control method for a light-emitting apparatus comprising a light-emitter, and a charging unit that has a capacitor and is charged with electrical charge for causing the light-emitter to emit light, the method comprising:

switching to perform one of a first charging control and a second charging control, wherein the first charging control charges the charging unit until a charging voltage of the charging unit reaches a target first level and then maintains the charging level at the first level, and the second charging control charges the charging unit until the charging voltage reaches the first level when the charging voltage reaches a second level lower than the first level.