Calibration apparatus, calibration method, and recording medium having recorded thereon calibration program

Patent metadata

Field	Value
Publication number	US-12270685-B2
Application number	US-202217876592-A
Country	US
Kind code	B2
Filing date	Jul 29, 2022
Priority date	Aug 26, 2021
Publication date	Apr 8, 2025
Grant date	Apr 8, 2025

Abstract

Provided is a calibration apparatus comprising: a driving control unit to drive an object provided with a lens in a movable range for moving the object in an optical axis-direction by sequentially controlling a plurality of drive units configured to drive the object within each of a plurality of sections into which the movable range is divided, in calibration of a drive apparatus including: the plurality of drive units; and a magnetic field detection unit configured to detect a magnetic field corresponding to a position of the object; a position acquisition unit to acquire position data of the object; a magnetic field acquisition unit to acquire magnetic field data corresponding to a position of the object; and a generating unit to generate, based on the position data and the magnetic field data, end point information to determine a driving range in each of the plurality of sections.

First claim

What is claimed is:

1. A calibration apparatus comprising:
a driving control unit configured to drive an object provided with a lens in a movable range for moving the object in an optical axis-direction by sequentially controlling a plurality of drive units configured to drive the object within each of a plurality of sections into which the movable range is divided, in calibration of a drive apparatus including: the plurality of drive units; and a magnetic field detection unit configured to detect a magnetic field corresponding to a position of the object;
a position acquisition unit configured to acquire position data indicating data regarding a position of the object;
a magnetic field acquisition unit configured to acquire magnetic field data indicating a magnetic field corresponding to a position of the object; and
a generating unit configured to generate, based on the position data and the magnetic field data, end point information indicating a value of the magnetic field data when the object is located at each of end points of the plurality of sections, to determine a driving range in each of the plurality of sections by using the end point information.

2. The calibration apparatus according to claim 1 , wherein the driving control unit is configured to control, in accordance with a position of the object, one drive unit responsible for a section in which the object is located among the plurality of drive units as a control target.

3. The calibration apparatus according to claim 2 , further comprising a switch decision unit configured to decide a switch of the control target based on the position data, wherein
the driving control unit is configured to switch the control target based on a decision result of the switch decision unit.

4. The calibration apparatus according to claim 3 , wherein the switch decision unit is configured to decide a switch of the control target to a drive unit responsible for a next section when the object moved from an end to an opposite end in each section.

5. The calibration apparatus according to claim 4 , wherein the switch decision unit is configured to decide that the object has moved to the opposite end when the position data exceeds a prestored standard.

6. The calibration apparatus according to claim 4 , wherein
the magnetic field detection unit includes a plurality of magnetic sensors each of which is associated with one of the plurality of drive units, and
the magnetic field acquisition unit is configured to acquire the magnetic field data from a magnetic sensor associated with the drive unit having become the control target.

7. The calibration apparatus according to claim 5 , wherein
the magnetic field detection unit includes a plurality of magnetic sensors each of which is associated with one of the plurality of drive units, and
the magnetic field acquisition unit is configured to acquire the magnetic field data from a magnetic sensor associated with the drive unit having become the control target.

8. The calibration apparatus according to claim 6 , wherein the magnetic field acquisition unit is configured to acquire the magnetic field data further from a magnetic sensor associated with the drive unit responsible for the next section.

9. The calibration apparatus according to claim 6 , wherein
each of the plurality of magnetic sensors is composed of a sensor element group consisting of a plurality of sensor elements, and
the magnetic field acquisition unit is configured to acquire the magnetic field data from at least one sensor element of the plurality of sensor elements.

10. The calibration apparatus according to claim 9 , wherein each of the plurality of sensor elements is arranged out of alignment with each other in an optical axis-direction and a direction crossing with the optical axis-direction.

11. The calibration apparatus according to claim 1 , wherein the generating unit is configured to generate the end point information by using a regression analysis using the position data and the magnetic field data.

12. The calibration apparatus according to claim 1 , wherein the position acquisition unit is configured to acquire, as the position data, at least one of measurement data of a measured position of the object or a magnetic field generated when the object moves.

13. The calibration apparatus according to claim 1 , further comprising the drive apparatus.

14. The calibration apparatus according to claim 13 , wherein
each of the plurality of drive units includes: a drive coil configured to drive a magnet provided for the object; and a driver configured to supply a drive current to the drive coil, and
the driving control unit is configured to control the drive current to be supplied from the driver to the drive coil.

15. The calibration apparatus according to claim 14 , wherein the driver is configured to be capable of inverting a direction of the drive current to be supplied to the drive coil in response to a control command from the driving control unit.

16. The calibration apparatus according to claim 15 , wherein the driving control unit is configured to gradually increase a magnitude of the drive current when the driving control unit causes the object to move from an end to an opposite end in each section.

17. The calibration apparatus according to claim 15 , wherein the driving control unit is configured to gradually decrease a magnitude of the drive current when the driving control unit causes the object to move from an end to an opposite end in each section.

18. The calibration apparatus according to claim 1 , further comprising an adjustment unit configured to adjust the end point information in response to feedback control having been performed based on the magnetic field data.

19. A calibration method comprising:
driving an object provided with a lens in a movable range for moving the object in an optical axis-direction by sequentially controlling a plurality of drive units configured to drive the object within each of a plurality of sections into which the movable range is divided, in calibration of a drive apparatus including: the plurality of drive units; and a magnetic field detection unit configured to detect a magnetic field corresponding to a position of the object;
acquiring position data indicating data regarding a position of the object;
acquiring magnetic field data indicating a magnetic field corresponding to a position of the object; and
generating, based on the position data and the magnetic field data, end point information indicating a value of the magnetic field data when the object is located at each of end points of the plurality of sections, to determine a driving range in each of the plurality of sections by using the end point information.

20. A non-transitory recording medium having recorded thereon a calibration program, executed by a computer, for causing the computer to function as:
a driving control unit configured to drive an object provided with a lens in a movable range for moving the object in an optical axis-direction by sequentially controlling a plurality of drive units configured to drive the object within each of a plurality of sections into which the movable range is divided, in calibration of a drive apparatus including: the plurality of drive units; and a magnetic field detection unit configured to detect a magnetic field corresponding to a position of the object;
a position acquisition unit configured to acquire position data indicating data regarding a position of the object;
a magnetic field acquisi

Assignees

• Asahi Kasei Microdevices Corp

Inventors

• Okada Keita
• Hara Takahito

Classifications

• G01D5/244

  influencing characteristics of pulses or pulse trains; generating pulses or pulse trains · CPC title

• G03B13/36

  Autofocus systems · CPC title

• G03B2205/0069

  using electromagnetic actuators, e.g. voice coils · CPC title

• G03B5/04

  Vertical adjustment of lens; Rising fronts · CPC title

• G05D3/125

  using discrete position sensor · CPC title