JPH0571706U - Image processing type measuring machine - Google Patents

Abstract

(57) [Summary] [Object] To provide an image processing type measuring instrument capable of changing the angle of illumination light with respect to an object to be measured with a simple and inexpensive structure. A light generating means 46 for generating illumination light radially outward with respect to the optical axis of the optical system 37, and an optical axis direction with the light generating means 46 for reflecting the illumination light to condense it on the optical axis. The reflecting member 52 having the ring-shaped reflecting surface 53 that reflects the illumination light at different angles in accordance with the relative position, and the reflecting member 52 and the light generating means 46 are differentially held with the condensing point at a fixed position. And a drive means 68 for moving. Reflective member 5
Since the relative positions of the two and the light generating means 46 are changed only by moving them differentially, it is possible to change the incident angle at that point while keeping the condensing point at a fixed position.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an image processing type measuring machine. Specifically, in an image processing type measuring instrument that measures the size and shape of the measured object from the image of the measured object obtained by the optical system, illuminate from a direction inclined at a predetermined angle with respect to the optical axis of the optical system. The present invention relates to an improvement of an illumination device that irradiates light on an object to be measured, and in particular, makes it possible to clearly draw shadows such as edges of the object to be measured.

[0002]

[Background technology]

 An image processing type measuring instrument that optically magnifies the measurement site of the DUT using a magnifying optical system and measures the dimensions and shape of the DUT from the magnified image, such as a tool microscope, projector, visual three-dimensional In measuring machines and the like, illumination of an object to be measured plays an extremely important role in obtaining a magnified image of the object to be measured.

Conventionally, as an illumination system in an image processing type measuring instrument, a vertical epi-illumination system is known, in which illumination light is irradiated to an object to be measured from almost directly above the object to be measured. However, this vertical epi-illumination method is often used when measuring an object to be measured that has a relatively simple shape, and the object to be measured has a complicated shape, for example, an object to be measured that has many edge portions. When measuring (step-like objects), the shadow of the edge may not be clearly depicted on the display device.

Therefore, as a solution to this, by illuminating the object to be measured with illumination light from a direction tilted at a predetermined angle with respect to the optical axis of the magnifying optical system, the shadow of the edge portion can be clearly detected. Such a method has been proposed. For example, the technical idea is disclosed in US Pat. No. 4,567,551. This is a method in which illumination light is output from a light source in a substantially horizontal direction, and the illumination light is reflected obliquely downward by a fixed mirror, and then refracted by a glass plate or the like to irradiate the DUT.

However, even in this case, since the irradiation angle of the illumination light to the object to be measured is constant, the image of the edge portion cannot be clearly drawn on the display device depending on the shape of the edge portion. For example, if the DUT has a shallow cylindrical edge portion such as a coin, the shadow of the edge portion cannot be clearly drawn. Therefore, the image depicted on the display device loses the stereoscopic effect, and it becomes difficult to accurately measure the size and shape of the object to be measured.

Therefore, the present applicant has previously proposed JP-A-2-236405 as a solution to such a problem. This is provided with a shape recognition means for recognizing the shape of the object to be measured on the support base, and also includes a movable mirror supported so as to be tiltable. The structure is such that an illuminating means for illuminating the illuminating light is provided so as to be able to move up and down with respect to the shape recognizing means, and an angle changing means for changing the tilt angle of the movable mirror in association with the raising and lowering of the illuminating means.

[0007]

[Problems to be solved by the device]

 In the above-mentioned Japanese Patent Laid-Open No. 2-236405, the irradiation angle of the illumination light to the object to be measured can be changed by the inclination angle of the movable mirror of the illumination means. However, for example, when illuminating light from around the cylindrical edge of a DUT to emphasize the shadow of the shallow cylindrical edge of the DUT, the illumination should be on the same circle around the optical axis of the shape recognition means. Since it is necessary to dispose a plurality of movable mirrors at the same time, there is a drawback that the number of parts increases and the number of assembling steps increases.

Moreover, with respect to the angle changing means for changing the tilt angle of the movable mirror, the tilt angles of the plurality of movable mirrors have to be controlled simultaneously with the ascending / descending of the illumination means. However, there is a drawback in that the device becomes complicated, the device becomes large in size, and the cost is increased.

It is an object of the present invention to provide an image processing type measuring machine which solves such a conventional problem, has a small number of parts, and can be simply and inexpensively constructed. ..

[0010]

[Means for Solving the Problems]

 Therefore, the image processing type measuring instrument of the present invention is an image processing type measuring instrument for measuring the size and shape of the measured object from the image of the measured object obtained by the optical system. Light generating means for radially radiating the illuminating light outward with respect to the center, and concentric with the optical axis and reflecting the illuminating light from the light generating means to condense on the optical axis, and A reflecting member having a ring-shaped reflecting surface that reflects the illumination light from the light generating means at different angles according to the relative position in the optical axis direction with the generating means, and the condensing point are held in a fixed position. And driving means for differentially moving the light generating means and the reflecting member along the optical axis direction.

[0011]

[Action]

 If the image of the object to be measured obtained by the optical system is not clear, the driving means is driven. Then, the light generating means and the reflecting member are differentially moved along the optical axis direction of the optical system. As a result, the relative position of the light generating means and the reflecting member in the optical axis direction changes, so that the illumination point is illuminated at that focusing point position while the focusing point of the illumination light is kept at a fixed position on the optical axis. The incident angle of light is changed. Therefore, the incident angle of the illumination light at the focal point fixed position can be changed without changing the amount of the illumination light at the fixed position. That is, since the illumination light can be emitted at an appropriate angle according to the shape of the edge of the object to be measured, the image of the edge of the object to be measured can be clearly drawn without impairing the stereoscopic effect.

[0012]

【Example】

 Preferred embodiments of the image processing type measuring instrument of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 shows an image processing type measuring machine of this embodiment. The image processing type measuring machine 10 is roughly composed of a microscope 20 which is a tool microscope and an image display device 90.

The microscope 20 includes a support 21 having an L-shaped side surface. On a base portion 21A that protrudes from the lower part of the front surface of the support base 21 toward the front, a mount base 22 on which an object 25 to be measured is mounted is installed. The stage 22 is composed of an XY table that is movable in two orthogonal axes in a horizontal plane, that is, in the left-right direction (X-axis direction) and the front-back direction (Y-axis direction), and in each axial direction. The moving amount can be set or measured by the X-axis micrometer head 23 and the Y-axis micrometer head 24.

A vertical movement guide 27 having a vertical movement knob 26 is provided on the upper front surface of the support base 21. The vertical movement guide 27 supports a side-U-shaped support frame 31 that is vertically movable via a rack, a pinion, or the like (not shown) when the vertical movement knob 26 is rotated. At the front open end of the support frame 31, columnar bodies 32 are respectively interposed at the left and right ends of the support frame 31 to reinforce the support frame 31, and the open side of the support frame 31 has a planar U-shaped cover. 33 can be attached.

A magnifying optical system 37 is provided at the center of the support frame 31. The magnifying optical system 37 includes an objective lens 34 protruding below the support frame 31, an imaging lens 35 provided coaxially with the objective lens 34, and an imaging lens 35 provided coaxially with the imaging lens 35. It is composed of a CCD camera 36 protruding above 31. The image display device 90 is connected to the CCD camera 36 via a wiring cord 38.

Inside the support frame 31, as shown in FIG. 2, a pair of lift shafts 42 and 43 are supported slidably in the vertical direction via a holding block 41 provided in the support frame 31. Has been done. A ring-shaped holding ring 45 is attached to the lower end of the elevating shaft 42 via an L-shaped bracket 44 coaxially with the optical axis of the optical system 37. On the lower surface of the holding ring 45, ring-shaped light generating means 46 that radially radiates illumination light outwardly around the optical axis is arranged concentrically with the optical axis. As shown in FIG. 3, the light generating means 46 includes a ring-shaped member 47 and a plurality of optical fibers 48 that radially radiate illumination light outward from the outer peripheral surface of the ring-shaped member 47 about the optical axis. It consists of and. A plurality of optical fibers 48 are bundled and passed through the inside of the holding ring 45 to be housed in a ring-shaped member 47 in an annular shape, and each end face is attached to the outer peripheral surface of the ring-shaped member 47 one by one. It is aligned along the line.

A ring-shaped reflecting member 52 is attached to the lower end of the elevating shaft 43 via an L-shaped bracket 51 concentrically with the optical axis of the optical system 37. The reflecting member 52 reflects the illumination light from the light generating means 46 toward the inside to focus the illumination light on the optical axis, and at the same time, reflects the relative position of the illumination light from the light generating means 46 in the optical axis direction. It has a ring-shaped reflecting surface 53 that reflects the illumination light from the generating means 46 at different angles. A cover 54 is attached to the upper surface of the reflecting member 52 to cover the light generating means 46 and the upper portion of the holding ring 45. The cover 54 is formed with escape holes 55 and 56 for the L-shaped bracket 44 and the optical fiber 48, respectively.

Inside the holding block 41, the pinions 63, which mesh with the racks 61, 62 formed along the longitudinal direction of the opposite side surfaces of the pair of lifting shafts 42, 43 and have the same number of teeth n, are provided. 64 are rotatably supported. A motor 66 is connected to the shaft 65 of the pinion 64, and a pinion 67 meshing with the pinion 63 and having more teeth than the n is provided. Therefore, if the elevating shafts 42 and 43 descend from the state of FIG. 2, the descending amount of the elevating shaft 42 is larger than the descending amount of the elevating shaft 43. Here, the light generating means 46 and the reflecting member 52 are provided so that the converging point is held at a fixed position by the lifting shafts 42, 43, the racks 61, 62, the pinions 63, 64, 67 and the motor 66. A drive unit 68 that moves differentially along the optical axis direction is configured.

The image display device 90 controls the driving of the CRT 91 and the motor 66, controls the light amount of the light generating means 46, and displays the signal from the CCD camera 36 on the CRT 91. It is composed of a control device 92. The control device 92 is provided with an operation unit 93 including a knob and a switch for performing each of the above controls at its front portion.

Next, the operation of this embodiment will be described. In the measurement, the X-axis and Y-axis micrometer heads 23, 24 of the stage 22 are set so that the object 25 to be measured placed on the stage 22 faces the objective lens 34. I'll do it. Further, the vertical movement knob 26 is rotated so that the measurement site of the object to be measured 25 is located at the focal position of the objective lens 34.

The illumination light radially output outward from the light generating means 46 about the optical axis is reflected inward by the reflecting surface 53 of the reflecting member 52, and then the object to be measured on the optical axis. It is reflected at 25. Then, the light enters the CCD camera 36 through the objective lens 34 and the imaging lens 35, is converted into an electric signal here, and then is input to the control device 92 of the image display device 90. As a result, the image of the DUT 25 is displayed on the CRT 91.

Here, when the image of the object to be measured 25 displayed on the CRT 91 is not clear, for example, when the shadow of the edge portion of the object to be measured 25 is not clear, the operation unit 93 of the control device 92 is used. Is operated to drive the motor 66 of the drive means 68. Then, the pair of lifting shafts 42, 43 are differentially moved via the pinions 63, 64, 67. At this time, for example, if the elevating shafts 42 and 43 descend, the descending amount of the elevating shaft 42 becomes larger than the descending amount of the elevating shaft 43. One is greatly lowered along the optical axis direction.

Then, as shown in the states of FIGS. 4 (A), (B), and (C), the reflecting surface 53 of the reflecting member 52 corresponds to the position of the light generating means 46 in the optical axis direction. Since the radial illumination light from is reflected inward at different angles, the incident angle of the illumination light at the focal point position changes while the focal point on the optical axis is kept at a fixed position. Therefore, the illumination light can be emitted at an appropriate angle according to the shape of the edge of the object to be measured 25, and the image of the edge of the object to be measured 25 can be clearly drawn without impairing the stereoscopic effect. it can.

For example, in the case where the edge of the DUT 25 is shallow, the incident angle of the illumination light to the DUT 25 becomes shallow when the inclination angle θ of the illumination light is made small. The shadow of the edge part of can be clearly drawn. Moreover, in any of the states of FIGS. 4A, 4B, and 4C, the reflecting surface 53 of the reflecting member 52 allows the radial illumination light from the light generating means 46 to be directed inward and on the optical axis. Since the light can be focused at a fixed position, the amount of illumination light for the object to be measured 25 does not change.

Therefore, according to the present embodiment, the light generating means 46 for radially radiating the illuminating light centering on the optical axis of the optical system 37 is provided concentrically with the optical axis and outside A reflecting member 52 having a ring-shaped reflecting surface 53 that reflects the illumination light inward toward the optical axis, condenses it on the optical axis, and reflects the illumination light at different angles depending on the position of the illumination light in the optical axis direction. Since the driving means 68 is provided for moving the reflecting member 52 and the light generating means 46 differentially in the optical axis direction so that the condensing point is held at a fixed position, the reflecting means is driven by the driving means 68. If 52 and the light generating means 46 are moved differentially, the relative position of the light generating means 46 and the reflecting member 52 in the optical axis direction changes, so that the ring-shaped reflecting surface 53 of the reflecting member 52 collects the light. The light spot is kept in a fixed position on the optical axis.

That is, since the incident angle of the illumination light at the focal point position is changed while the focal point is kept at the fixed position on the optical axis, the light amount of the illumination light with respect to the DUT 25 is changed. It is possible to change the angle of the illumination light with respect to the DUT 25 without changing. Therefore, the illumination light can be emitted at an appropriate angle according to the shape of the edge of the DUT 25, and the image of the edge of the DUT 25 can be drawn clearly without impairing the stereoscopic effect. it can.

Further, the structure capable of irradiating the measurement site of the object to be measured 25 with the illumination light from the surroundings may be configured only by the light generating means 46, the reflecting member 52 having the ring-shaped reflecting surface 53, and the driving means 68. As a result, the number of parts can be reduced, which can contribute to a reduction in the number of assembly steps. Moreover, as for the driving means 68, it is sufficient that the light generating means 46 and the reflecting member 52 are differentially moved in the same direction, that is, the driving means 68 is differentially moved in the optical axis direction of the optical system 37. Therefore, the racks 61 and 62 formed on the elevating shafts 42 and 43 and the pinions 63, 64 and 67 are sufficient, and there is an advantage that they can be easily and inexpensively constructed.

The present invention is not limited to the configuration of the above embodiment, and various improvements and design changes can be made without departing from the scope of the present invention.

For example, as the light generating means 46, as shown in FIG. 5, a plurality of optical fibers 48 are divided into a plurality of sections, and for example, an angle range of 90 degrees is divided into four sections, The light amount can be easily adjusted by independently controlling the turning on and off of the light source that introduces light into the optical fiber in each section. Further, instead of the optical fiber 48, light emitting elements such as light emitting diodes may be arranged in a line or a plurality of lines along the outer peripheral surface of the ring-shaped member 47. By doing so, it is possible to easily turn on and off each light emitting element, which is advantageous in that the light quantity of the light generating means 46 can be finely adjusted.

Further, the driving means 68 is not limited to the one using the rack and the pinion described in the above embodiment, but it is possible to differentially move the pair of lifting shafts 42, 43 in the optical axis direction. It doesn't matter. Further, instead of the CCD camera 36, an image orthe like may be used.

Further, the image processing type measuring machine according to the present invention is not limited to the one applied to the tool microscope as in the above-mentioned embodiment, but other types of optical measurement such as a projector and a three-dimensional measuring machine. It can also be applied to machines.

[0032]

[Effect of the device]

 As described above, according to the image processing type measuring instrument of the present invention, the number of parts is small, and the configuration can be simple and inexpensive.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a main part of FIG.

FIG. 3 is a perspective view showing a light generating means.

FIG. 4 is a diagram for explaining the relationship between a light generating means and a reflecting member.

FIG. 5 is a perspective view showing another example of the light generating means.

[Explanation of symbols]

 25 Object to be Measured 37 Optical System Means 46 Light Generation Means 52 Reflecting Member 53 Reflecting Surface 68 Driving Means

Claims (1)

[Scope of utility model registration request] 1. An image processing type measuring instrument for measuring the size, shape, etc. of an object to be measured from an image of the object to be measured obtained by an optical system, wherein the image processing type measuring machine radially radiates outward around the optical axis of the optical system. A light generating means for generating illumination light, concentric with the optical axis, and reflecting the illumination light from the light generating means to condense on the optical axis, and the optical axis with the light generating means. A reflecting member having a ring-shaped reflecting surface that reflects the illumination light from the light generating means at different angles according to the relative position in the direction, and the light generating means and the reflecting member so that the condensing point is held at a fixed position. An image processing type measuring instrument, comprising: