TWI427399B - Distance measuring device - Google Patents

Description

Distance measuring fixture

The invention relates to a distance measuring fixture, in particular to a distance measuring fixture capable of measuring a distance that a lens module moves when focusing at different angles.

The camera module with autofocus function has been widely used in the field of imaging, especially in digital camera devices. With the increasing use of photographic equipment, the focus accuracy requirements of camera modules are also increasing, and it is necessary to measure and calibrate various parameters of the camera module. (See Camera calibration with a motorized zoom lens, Pattern Recognition, 2000. Proceedings. 15th International Conference on Volume 4, 3-7 Sept. 2000 Page(s): 495-498 vol. 4)

In the manufacturing process of the camera module with autofocus function, in order to measure the focus accuracy, it is usually necessary to compare the lens module of the camera module under the same focus parameter when the camera module is used under various angles. Whether the distance moved is the same. In particular, it is necessary to measure the distance that the lens module moves when focusing when it has a different angle from the level surface. However, there is currently no relevant measuring fixture for measuring the consistency of the moving distance of the lens module when focusing at different angles.

In view of this, it is necessary to provide a lens module for measuring the focusing device at different angles. The distance of the distance moved when focusing down is used to measure the fixture.

A distance measuring fixture for measuring the distance a lens module moves when focusing at different angles. The distance measuring fixture comprises a fixing base, a rotating plate, a carrying platform, a distance measuring device and a rotating shaft fixed to the rotating plate through the fixing base. The mount remains stationary during the measurement process and the rotating plate has a non-horizontal fixed surface. The carrying platform and the distance measuring device are fixed on opposite ends of the fixing surface, and the carrying platform is used for fixing the lens module, and the distance measuring device is aligned with the lens module.

Compared with the prior art, the distance measuring jig of the present invention fixes the carrying platform and the lens module and the distance measuring device carried thereon to opposite ends of the fixed surface of the rotating plate, and measures the distance that the lens module moves when focusing. The rotating plate is also fixed to a rotating shaft. When the rotating plate is fixed, the angle between the carrying platform fixed on the fixing surface and the lens module carried thereon and the horizontal plane is changed, so that the lens module can be measured to focus at different angles. The distance to move.

100‧‧‧Distance measuring fixture

10‧‧‧ Fixed seat

20‧‧‧Rotating plate

21‧‧‧Fixed surface

30‧‧‧Loading station

40‧‧‧Ranging device

50‧‧‧Rotary axis

200‧‧‧ camera module

FIG. 1 is a schematic perspective view of a distance measuring jig provided by an embodiment of the present invention.

Figure 2 is a side elevational view of the distance measuring fixture of Figure 1.

The technical solution will be further described in detail below with reference to the accompanying drawings and embodiments.

Referring to FIG. 1 and FIG. 2 , the distance measuring jig 100 of the embodiment of the present invention is used to measure the distance that the lens module in the camera module 200 moves when focusing at different angles.

The camera module 200 includes a lens module and an autofocus motor. When focusing, from The moving focus motor drives the lens module to move up and down along its optical axis.

The distance measuring fixture 100 includes a fixing base 10, a rotating plate 20, a loading platform 30, a distance measuring device 40, and a rotating shaft 50 passing through the fixing base 10 and fixed to the rotating plate 20. The rotating plate 20 has a fixing surface 21, and the loading platform 30 and the distance measuring device 40 are fixed at opposite ends of the fixing surface 21.

The mount 10 remains stationary during the measurement process and has a through hole for the rotary shaft 50 to pass through. In the present embodiment, when the distance measuring jig 100 is used, the fixing base 10 is perpendicular to the horizontal plane and the rotating shaft 50, and the horizontal plane is a plane perpendicular to the gravitational acceleration.

The rotating plate 20 is coupled to the fixing base 10. The fixing surface 21 of the rotating plate 20 faces away from the fixing base 10. The fixing surface 21 is not parallel to the horizontal plane when it is used by the distance measuring jig 100. In the present embodiment, the fixing surface 11 is perpendicular to the horizontal plane and the rotating shaft 50.

The carrying platform 30 is fixed to one end of the fixing surface 21 for carrying and fixing the camera module 200. In the present embodiment, the carrying platform 30 is a flat plate that is perpendicular to the fixing surface 21 of the rotating plate 20. The carrier 30 has two surfaces, one of which faces the distance measuring device 40 and the other of which faces away from the distance measuring device 40. When the camera module 200 is being carried against the surface of the distance measuring device 40, there is no through hole on the surface. When the camera module 200 is carried on the surface facing away from the distance measuring device 40, the surface has a through hole coaxial with the lens module in the camera module 200.

The distance measuring device 40 is configured to measure a distance that the lens module in the camera module 200 moves when focusing. The distance measuring device 40 is aligned with the lens module, and when the lens module is in focus movement When the measurement signal is first sent and the distance S1 between the lens module and the distance measuring device 40 is measured, the measurement signal is sent and the distance S2 between the lens module and the distance measuring device 40 after the focus is detected. It can be understood that S=S2-S1 is the moving distance S of the lens module during the focusing process.

In the present embodiment, the distance measuring device 40 is a laser range finder, which is composed of a laser emitting system and a detecting system. When working, the laser emitting system emits a laser, which is reflected by a reflecting surface of the lens module and returned. The detector receives. The distance between the lens module and the distance measuring device 40 can be determined by measuring the time elapsed from the laser reflection to the reception of the reflected light.

One end of the rotating shaft 50 is fixed to the rotating plate 20 through the fixing base 10 to drive the rotating plate 20 to rotate. In the present embodiment, when the distance measuring jig 100 is used, the rotating shaft 50 is parallel to the horizontal plane and perpendicular to the fixing surface 21. Therefore, the fixing surface 21 is a rotating surface of the rotating plate 20, which can make the lens module and the horizontal plane have an arbitrary angle. The other end of the rotating shaft 50 can be connected to a driving mechanism. In the embodiment, the driving structure is a stepping motor for controlling the number of rotating steps. By controlling the number of rotating steps, the lens module and the horizontal plane can be precisely controlled. The angle between the two.

During the measurement, the driving shaft 50 drives the rotating plate 20 to rotate at an angle such that the angle between the lens module of the camera module 200 and the horizontal plane is an angle A1, and the lens module is measured at a certain angle at the angle A1. When focusing under the parameter, its moving distance B1 during focusing. The driving rotating plate 10 is further rotated by a certain angle, so that the angle between the lens module of the camera module 200 and the horizontal plane is an angle A2, and at this angle, when the A2 measures the focusing of the lens module under a certain focusing parameter, B2 during the focusing process. It can be understood that the lens module of the camera module 200 and the water are rotated by driving the rotating plate 10 to rotate. The angle between the planes is any angle, and the measurable distance of the lens module when focusing at any angle. By comparing the moving distance of the lens module at different angles, it is possible to determine the focusing accuracy of the lens module when it is used at different angles.

Compared with the prior art, the distance measuring jig of the present invention fixes the carrying platform and the lens module and the distance measuring device carried thereon to opposite ends of the fixed surface of the rotating plate, and measures the distance that the lens module moves when focusing. The rotating plate is also fixed to a rotating shaft. When the rotating plate is fixed, the angle between the carrying platform fixed on the fixing surface and the lens module carried thereon and the horizontal plane is changed, so that the lens module can be measured to focus at different angles. The distance to move.

It is to be understood that those skilled in the art can make various other changes and modifications in accordance with the present invention, and all such changes and modifications are intended to fall within the scope of the appended claims.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

100‧‧‧Distance measuring fixture

10‧‧‧ Fixed seat

20‧‧‧Rotating plate

21‧‧‧Fixed surface

30‧‧‧Loading station

40‧‧‧Ranging device

50‧‧‧Rotary axis

200‧‧‧ camera module

Claims (8)

A distance measuring fixture for measuring a distance that a lens module moves when focusing at different angles, wherein the distance measuring fixture comprises a fixing seat, a rotating plate, a carrying platform, a distance measuring device and a a rotating shaft fixed to the rotating plate through the fixing seat, the fixing seat is kept stationary during the measuring process, the rotating plate has a non-horizontal fixing surface, and the bearing table and the distance measuring device are fixed on the fixing surface At both ends, the carrier is used to fix the lens module, and the distance measuring device is aligned with the lens module. The distance measuring jig according to claim 1, wherein the distance measuring jig further comprises a driving structure connected to the rotating shaft to drive the rotating shaft to rotate. The distance measuring fixture of claim 2, wherein the driving structure is a stepping motor. The distance measuring fixture according to claim 1, wherein the distance measuring device is a laser range finder. The distance measuring jig according to claim 1, wherein the carrying table is integrally formed with the rotating plate. The distance measuring fixture of claim 1, wherein the carrier has two surfaces, one of the surfaces for carrying the lens module and facing the distance measuring device. The distance measuring fixture of claim 1, wherein the carrier has two surfaces, one of the surfaces for carrying the lens module and facing away from the distance measuring device, the surface having a through hole. The distance measuring fixture according to claim 1, wherein the fixed surface of the rotating plate and the water The plane is vertical.