CN203149185U - Laser Assisted Autofocus Lenses - Google Patents

Abstract

The utility model provides an automatic focusing camera lens is assisted to laser is applied to image formula measuring apparatu camera lens auto focus field. The device consists of a lens for an image measuring instrument, a laser dot indicator, a CCD camera, a motion controller, a servo motor, a motion mechanism and focusing control software. When the lens moves up and down relative to an object to be imaged, because the laser indicator and the optical axis of the lens form a certain included angle, light spots of the laser indicator move along with the lens position imaged by the CCD camera. And obtaining a rough focal plane position through the trigonometric function relation among the spot position, the included angle of the laser indicator and the optical axis of the lens and the focal length of the lens. And then accurately focusing near the rough focal plane by an image definition judgment algorithm. The lens combines two methods of laser-assisted coarse positioning and image definition judgment algorithm accurate positioning, and solves the problem of low focusing speed of a common automatic focusing lens.

Description

Translated fromChinese

激光辅助自动对焦镜头Laser Assisted Autofocus Lenses

技术领域technical field

本实用新型一种激光辅助自动对焦镜头，与影像测量仪上用的镜头有关。利用激光辅助可以实现自动对焦的镜头，属于镜头。 The utility model relates to a laser-assisted automatic focusing lens, which is related to the lens used in an image measuring instrument. A lens that can achieve automatic focus with laser assistance belongs to the lens. the

背景技术Background technique

在影像测量领域中，镜头对焦始终是一项费事效率又低的问题。因为影像测量仪上用的镜头放大倍数大景深非常小，通常情况下景深只有0.02mm。对焦稍微不准便造成影像模糊不清，在影像不清晰的情况下进行测量，由于影像背景和被测工件边界不清晰便造成测量误差。影像式测量仪的用户想减少这个误差的影响就必须不断地调整镜头焦距。由于镜头景深小的原因经常容易调过头，便会出现调过来又调过去，调了好久还没有调好焦距的问题。在这个情况下便出现了通过软件辅助对焦的镜头，在镜头慢速上下移动的过程中软件不断的计算当前位置的CCD影像清晰度，在影像清晰度最好的地方就是镜头对焦最好的位置。但是这又有一个问题就是镜头上下移动速度不能太快，太快了CCD相机还没有抓拍到一帧图像镜头就移动了太远的距离了，就造成了对焦不准确的问题。当前市场上难以解决对焦精度和效率同时兼顾的难题。 In the field of image measurement, lens focusing has always been a time-consuming and inefficient problem. Because the lens used on the image measuring instrument has a large magnification and the depth of field is very small, usually the depth of field is only 0.02mm. Slightly inaccurate focusing will cause blurred images. If the measurement is performed when the image is not clear, the measurement error will be caused by the unclear image background and the boundary of the measured workpiece. Users of image measuring instruments must constantly adjust the focal length of the lens if they want to reduce the influence of this error. Due to the small depth of field of the lens, it is often easy to over-adjust, and there will be a problem of adjusting the focus again and again, and the focus has not been adjusted for a long time. In this case, there is a software-assisted focusing lens. When the lens is moving up and down at a slow speed, the software continuously calculates the CCD image clarity at the current position. The place with the best image clarity is the best lens focus position. . But there is another problem that the lens cannot move up and down too fast. If the CCD camera moves too far before capturing a frame of image, it will cause inaccurate focusing. It is difficult to solve the problem of both focusing accuracy and efficiency in the current market. the

本实用新型一种激光辅助自动对焦镜头，可以利用激光指示器照射位置大概计算出镜头焦平面位置，首先快速移动镜头到达大概的焦平面位置，再利用CCD相机影像清晰度判断算法精确对焦。同时兼顾的对焦速度和对焦精度的要求。 The utility model relates to a laser-assisted auto-focus lens, which can roughly calculate the focal plane position of the lens by using the irradiation position of a laser pointer, firstly move the lens quickly to reach the approximate focal plane position, and then use the CCD camera image definition judgment algorithm to accurately focus. At the same time, it takes into account the requirements of focusing speed and focusing accuracy. the

发明内容Contents of the invention

本实用新型一种激光辅助自动对焦镜头，由影像测量仪用镜头、激光圆点指示器、CCD相机、运动控制器、伺服马达、运动机构、和对焦控制软件组成。 The utility model relates to a laser-assisted automatic focus lens, which is composed of a lens for an image measuring instrument, a laser dot indicator, a CCD camera, a motion controller, a servo motor, a motion mechanism, and focus control software. the

机械结构：CCD通过镜头接头和镜头连接，整组镜头再通过镜头加安装到运动机构的运动辐上，伺服马达通过联轴器连接到滚珠丝杆上，当伺服马达转动时，滚珠丝杆便一同转动，丝杆的转动又带动丝杆运动辐移动，丝杆运动辐的移动便推动了线性导轨上的镜头架上下移动。激光指示器以相当于镜头光轴方向固定角度安装到镜头上，在镜头上的CCD相机成像最清晰时，使激光指示器的光斑正好在CCD相机成像的图像正中央。 Mechanical structure: CCD is connected to the lens through the lens joint, and the whole set of lenses is then mounted on the moving spoke of the moving mechanism through the lens. The servo motor is connected to the ball screw through the coupling. When the servo motor rotates, the ball screw will Rotating together, the rotation of the screw mandrel drives the movement of the screw mandrel to move, and the movement of the movement of the screw mandrel pushes the lens holder on the linear guide rail to move up and down. The laser pointer is installed on the lens at a fixed angle corresponding to the optical axis of the lens. When the CCD camera on the lens has the clearest image, the light spot of the laser pointer is just in the center of the image formed by the CCD camera. the

电路连接：计算机通过USB接口连接运动控制器，运动控制器再通过电缆连接伺服控制器，伺服控制器也是通过电缆连接到伺服马达。CCD相机通过视频卡采集视频帧到计算机。 Circuit connection: The computer is connected to the motion controller through the USB interface, and the motion controller is connected to the servo controller through a cable, and the servo controller is also connected to the servo motor through a cable. The CCD camera collects video frames to the computer through the video card. the

控制链路：计算机软件通过运动控制器发送运动指令给伺服马达，伺服马达再推动镜头上下运动，从而就实现了镜头远离或靠近焦平面的动作。当镜头相对于需成像物体上下移动时，由于激光指示器和镜头光轴有一定夹角的原因，激光指示器的光斑在CCD相机成像的画面位置便会远离或接近图像的正中央。计算机通过软件CCD相机返回的视频帧就可以计算光斑位置，通过光斑位置，再发送指令控制移动镜头使镜头移动到焦平面位置。 Control link: The computer software sends motion commands to the servo motor through the motion controller, and the servo motor then drives the lens to move up and down, thus realizing the movement of the lens away from or close to the focal plane. When the lens moves up and down relative to the object to be imaged, due to the angle between the laser pointer and the optical axis of the lens, the light spot of the laser pointer will be far away from or close to the center of the image in the image of the CCD camera. The computer can calculate the spot position through the video frame returned by the software CCD camera, and then send instructions to control the moving lens to move the lens to the focal plane position through the spot position. the

附图说明Description of drawings

图1  本实用新型结构示意图。 Figure 1 Schematic diagram of the structure of the utility model. the

图中标号： Labels in the figure:

1、镜头　              2、激光指示器1. Lens 2. Laser pointer

3、ＣＣＤ相机       4、伺服马达3. CCD camera 4. Servo motor

5、运动机构。5. Movement mechanism.

具体实施方式Detailed ways

首先本实用新型一种激光辅助自动对焦镜头，如图1所示，其具有一镜头1、激光指示器2、CCD相机3、伺服马达4和运动机构5组成。其中CCD相机3安装在镜头1上共同组成一个图像拾取单元，可以实时的拾取镜头下的影像传输到计算机，计算机再通过传输来的影像分析图像清晰度。激光指示器2和镜头1光轴夹角固定，激光指示器2在影像上便形成一个光斑。镜头1再安装在运动机构5上，运动机构5再和伺服马达4连接，计算机可以发送指令使伺服马达4旋转，伺服马达4的旋转会带动运动机构5做上下往复运动，镜头1会跟随运动机构5远离或靠近被对焦的物体。 First of all, the utility model is a laser-assisted auto-focus lens, as shown in FIG. Wherein the CCD camera 3 is installed on the lens 1 to jointly form an image pickup unit, which can pick up the image under the lens in real time and transmit it to the computer, and the computer analyzes the image definition through the transmitted image. The included angle between the laser pointer 2 and the optical axis of the lens 1 is fixed, and the laser pointer 2 forms a light spot on the image. The lens 1 is installed on the moving mechanism 5, and the moving mechanism 5 is connected with the servo motor 4. The computer can send instructions to make the servo motor 4 rotate. The rotation of the servo motor 4 will drive the moving mechanism 5 to reciprocate up and down, and the lens 1 will follow the movement. Mechanism 5 moves away from or approaches the object being focused. the

藉由上述之结构组合，本实用新型一种激光辅助自动对焦镜头，对焦过程分两步完成，一、粗定位：软件在CCD相机3拾取的图像中自动测量激光指示器2的光斑相对于图像中央偏差距离d。 根据三角函数通过偏差距离d、激光指示器2和镜头1光轴夹角（固定值а）可计算出镜头1到焦平面距离 L=d/tag(а)。再通过这个距离发指令给伺服马达4旋转，伺服马达4的旋转带动运动机构5上下快速移动，运动机构带动镜头1移动到焦距位置完成粗定位过程。二、精确定位：计算机发送指令给伺服马达4，使镜头1在刚刚粗定位的附近连续慢速的移动，同时计算机软件再通过影像清晰度判断算法不断的寻找CCD相机3拾取的影像的最清晰位置，找到最清晰位置后记录这个位置数值，停止焦平面搜索同时移动镜头1到焦平面位置，完成精确对焦过程。整个对焦程序便结束了。 By the combination of the above structures, the utility model is a laser-assisted autofocus lens. The focusing process is completed in two steps. One, rough positioning: the software automatically measures the light spot of the laser pointer 2 relative to the image in the image picked up by the CCD camera 3 Central deviation distance d. According to the trigonometric function, the distance from the lens 1 to the focal plane L=d/tag(а) can be calculated through the deviation distance d, the angle between the laser pointer 2 and the optical axis of the lens 1 (fixed value а). Then send instructions to the servo motor 4 to rotate through this distance, the rotation of the servo motor 4 drives the motion mechanism 5 to move up and down quickly, and the motion mechanism drives the lens 1 to move to the focal length position to complete the rough positioning process. 2. Accurate positioning: the computer sends instructions to the servo motor 4 to make the lens 1 move continuously and slowly near the rough positioning just now, and at the same time, the computer software continuously searches for the clearest image picked up by the CCD camera 3 through the image definition judgment algorithm After finding the clearest position, record the value of this position, stop the focal plane search and move the lens 1 to the focal plane position at the same time to complete the precise focusing process. The entire focusing procedure is over. the

Claims (2)

1. the auxiliary autofocus lens of laser is made up of with camera lens, laser dot indicator, CCD camera, motion controller, servo motor, motion and focusing control software image measurer; It is characterized in that: a laser designator has been installed on the camera lens.

2. the auxiliary autofocus lens of a kind of laser according to claim 1 is characterized in that: a cover servo motion mechanism has been installed on the camera lens.