JP2006154595A - Imaging optical apparatus and laser repair apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging optical apparatus uniformizing intensity distribution of laser light even in using laser light having strong coherence or laser light of short wavelength, and also to provide a laser repair apparatus incorporating the imaging optical apparatus. <P>SOLUTION: Regarding the laser CVD repair apparatus 1, a beam expander 4, an original quadrangular pyramid type prism 5, a variable slit part 6, an imaging relay lens 7, and an objective lens 8 are arranged in this order along the optical path of the laser light emitted from a laser oscillator 2, and a workpiece 50 is arranged in the focal position of the objective lens 8. The center axis of the prism 5 is aligned with the optical axis of the laser light 21b. A rotary driving motor 9 and a rotating mechanism part 10 are arranged to rotate the prism 5 around its own center axis as a rotating axis. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an imaging optical device that is incorporated in a laser repair device that repairs an object to be corrected by irradiating a laser beam, shapes the incident laser light into a repair shape, and guides the object to the object to be corrected, and this The present invention relates to a laser repair device incorporating an imaging optical device.

  Conventionally, laser CVD (Chemical Vapor Deposition) has been used to repair (repair) semiconductor devices and integrated circuits such as liquid crystal display (LCD) pixel circuits and photomasks for manufacturing these integrated circuits. : Chemical vapor deposition) Repair equipment is used. In this laser CVD repair device, a laser oscillator, an imaging optical device that shapes laser light emitted from the laser oscillator into a repair shape and guides it to the object to be corrected, and a CVD source gas is supplied to the object to be corrected A raw material gas supply means is provided.

  For example, in Patent Document 1, as the above-described imaging optical device, a nine-sided prism, an imaging lens, a mask, and a projection lens are arranged in this order along the optical path of laser light, and the focal position of the projection lens is set. An optical device for laser processing in which a workpiece is disposed is disclosed. In this laser processing optical device, the laser light is divided into nine parts by a nine-sided prism, and these nine parts are superimposed on one at a position between the nine-sided prism and the imaging lens. An image at the position superimposed on this one by the image lens is formed at the position of the mask, the laser light beam is shaped into a processed shape by this mask, and this processed shape is imaged on the workpiece by the projection lens. It has come to be. In Patent Document 1, the nine-sided prism splits the laser light into nine parts inside and near the imaging lens and the projection lens, so that the imaging lens and the projection lens can be prevented from being damaged. It is described.

  However, recently, with the miniaturization of integrated circuit devices, these integrated circuit devices and laser CVD repair devices used for correcting photomasks are required to have high-precision processing performance. In order to improve the processing performance of the laser CVD repair apparatus, improvement of the uniformity of the processed part is an extremely important factor. In order to ensure the uniformity of the processed part by laser CVD, it is conceivable to make the intensity distribution of the laser light irradiated to the processed part uniform and to uniformize the CVD source gas for the processed part.

  Patent Document 2 discloses a technique for making the intensity distribution of laser light uniform by using a quadrangular pyramid prism. 10A to 10D are diagrams showing an optical device described in Patent Document 2, in which FIG. 10A is an optical model diagram, and FIG. 10B is a diagram of laser light before passing through a quadrangular pyramid prism. The figure which shows the shape (henceforth an optical axis perpendicular | vertical shape) in a surface perpendicular | vertical to an optical axis, (c) is the top view which looked at the quadrangular pyramid prism from the optical axis direction, (d) was irradiated to the workpiece. It is a figure which shows the optical axis perpendicular | vertical shape of a laser beam.

  As shown in FIG. 10A, the optical device 101 is provided with a quadrangular pyramid prism 102, and a laser beam 103 a is incident on the quadrangular pyramid prism 102. The central axis of the quadrangular pyramid prism 102 coincides with the optical axis of the laser beam 103a. The laser beam 103b emitted from the quadrangular pyramid prism 102 is irradiated on the processing surface 104 of the workpiece. A line 105 shown in FIG. 10A represents the intensity distribution in the plane perpendicular to the optical axis of the laser beam 103a, and a line 106 represents the intensity distribution in the processed surface 104 of the laser beam 103b.

  As shown in FIGS. 10A to 10D, the optical axis vertical shape of the laser beam 103a before entering the quadrangular pyramid prism 102 is circular, and its intensity distribution is stronger in the central part than in the peripheral part. Gaussian distribution. When this laser beam 103a is incident on the quadrangular pyramid prism 102, the laser beam 103a is divided into four parts and each part is refracted in different directions and emitted as laser light 103b. Then, each part of the laser beam 103b overlaps on the processed surface 104 of the workpiece, the central part of the laser beam 103a becomes the peripheral part of the laser beam 103b, and the peripheral part of the laser beam 103a becomes the central part of the laser beam 103b. As a result, the shape perpendicular to the optical axis of the laser beam 103b becomes a square. Patent Document 2 describes that the intensity distribution of the laser beam 103b on the processed surface 104 is uniform, as indicated by a line 106 in FIG.

Japanese Patent Laid-Open No. 5-188318 (FIG. 1) Japanese Utility Model Publication No. 63-82216 (FIGS. 4 and 5)

  However, the conventional techniques described above have the following problems. Recently, since the integrated circuit to be repaired has been miniaturized, it is necessary to use laser light with high coherence (directivity) in the laser CVD repair device, and the work efficiency of repair has been improved. Therefore, it is required to use a short wavelength laser beam having a short wavelength and high energy. However, in the optical device 101 shown in FIG. 10A, when laser light having a short wavelength such as laser light having strong coherence or ultraviolet laser light having a wavelength in the ultraviolet region is used, the light passes through the quadrangular pyramid prism 102. After that, interference fringes appear at a constant pitch in the laser light 103b, and the uniformity of the intensity distribution of the laser light is greatly impaired.

  The present invention has been made in view of such problems, and an imaging optical device capable of making the intensity distribution of laser light uniform even when laser light or short wavelength laser light having high coherence is used, Another object of the present invention is to provide a laser repair device in which the imaging optical device is incorporated.

  An imaging optical device according to the present invention is incorporated in a laser repair device that repairs a correction target object by irradiating the laser beam, and forms the laser light into a repair shape and guides it to the correction target object. In the apparatus, a pyramid prism arranged so that its central axis coincides with the optical axis of the laser beam, a slit for shaping the laser beam condensed by the pyramid prism into a repair shape, An optical element for forming an image on the object to be corrected, and a rotating means for rotating the pyramidal prism with a central axis as a rotation axis.

  In the present invention, the rotating means rotates the pyramid prism so that the intensity distribution non-uniformity due to the interference fringes is temporally averaged, and the intensity distribution of the laser light irradiated to the object to be corrected is made uniform. be able to.

  Another imaging optical device according to the present invention is incorporated in a laser repair device that repairs a correction target object by irradiating the laser beam, and shapes the laser light into a repair shape and guides it to the correction target object. In the image optical device, a conical prism arranged such that a central axis thereof is inclined with respect to an optical axis of the laser light and the laser light passes through the apex thereof, and the condensate prism condensed by the conical prism A slit that shapes the laser beam into a repair shape, an optical element that forms an image of the slit on the object to be corrected, a rotating unit that rotates the conical prism around the optical axis of the laser beam, and It is characterized by having. The conical prism may be a conical prism.

  In the present invention, the conical prism is arranged such that its central axis is inclined with respect to the optical axis of the laser light and its apex passes through the apex, and the rotating means places the conical prism into the light of the laser light. By rotating about the axis, the cone-shaped prism rotates eccentrically. As a result, even when a conical prism is used as the conical prism, the influence of interference fringes can be eliminated and the intensity distribution of the laser light applied to the object to be corrected can be made uniform.

  The laser repair device according to the present invention is a laser repair device that repairs an object to be corrected by irradiating a laser beam, and shapes the laser oscillator and the laser beam emitted from the laser oscillator into a repair shape. An imaging optical device that guides the object to be corrected, and this imaging optical device is the imaging optical device according to the present invention described above.

  The laser repair apparatus according to the present invention further includes a source gas supply means for supplying a source gas of CVD to a position of the target object to be irradiated with the laser beam, and performs the repair by laser CVD. It may be a repair device.

  According to the present invention, the rotating means rotates the pyramid prism so that the influence of the interference fringes is eliminated and the object to be corrected is irradiated even if laser light or short wavelength laser light having strong coherence is used. The intensity distribution of the laser beam can be made uniform.

  Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings. First, a first embodiment of the present invention will be described. FIG. 1 is an optical model diagram showing a laser CVD repair apparatus according to the present embodiment, FIG. 2 is a front view and a side view showing a regular quadrangular pyramid prism shown in FIG. 1, and FIG. 3 is a variable diagram shown in FIG. It is a perspective view which shows a slit part.

  As shown in FIG. 1, the laser CVD repair apparatus 1 according to the present embodiment is provided with a laser oscillator 2, and the laser oscillator 2 and a workpiece 50 that is a correction target of the laser CVD repair apparatus 1. In the middle, an imaging optical device 3 is provided. The imaging optical device 3 shapes the laser beam emitted from the laser oscillator 2 into a repair shape and guides it to the workpiece 50. The work 50 is an integrated circuit such as a semiconductor device or an LCD pixel circuit. Further, the laser CVD repair apparatus 1 is provided with a raw material gas supply means (not shown) for supplying a raw material gas for CVD at a position where the laser beam is irradiated on the workpiece 50.

  In the imaging optical device 3, along the optical path of laser light emitted from the laser oscillator 2, a beam expander 4, a regular quadrangular pyramid prism 5, a variable slit portion 6, an imaging relay lens 7 and an objective lens 8 are provided. They are provided in this order, and the work 50 is arranged at the focal position of the objective lens 8. The beam expander 4 expands the beam diameter of the laser beam 21a emitted from the laser oscillator 2, collimates it (collimates it), and emits it as the laser beam 21b. The regular quadrangular pyramid prism 5 is arranged such that its apex is directed to the beam expander 4 side and its central axis coincides with the optical axis of the laser beam 21b. The variable slit portion 6 is disposed at a position where the beam diameter of the laser light 21c emitted from the regular quadrangular pyramid prism 5 is minimized.

  In the imaging optical device 3, the rotation drive motor 9 and the rotational movement of the rotation drive motor 9 are transmitted to the regular quadrangular pyramid prism 5, and the regular quadrangular pyramid prism 5 rotates around its central axis as a rotation axis. And a rotating mechanism unit 10 to be rotated. The rotation mechanism unit 10 is a machine part configured by, for example, a gear or a belt. The rotation drive motor 9 and the rotation mechanism unit 10 constitute rotation means, and the regular quadrangular pyramid prism 5 can be rotated at an arbitrary speed.

  As shown in FIG. 2, the regular quadrangular pyramid prism 5 is circular when viewed from the central axis direction, and four roof-like surfaces 5a to 5d are formed on the apex side thereof. The shapes of the surfaces 5a to 5d are equal to each other. When the laser beam 21b is incident on the regular quadrangular pyramid prism 5, the laser beam 21b is divided into four parts by the surfaces 5a to 5d, and each part is refracted in different directions and emitted as the laser beam 21c. . The laser beam 21c is emitted from the regular quadrangular pyramid prism 5 and then condensed so that the four divided portions overlap each other.

  As shown in FIG. 3, the variable slit portion 6 is provided with four slit members 11 a to 11 d, and the outer edge of the opening portion 12 is configured by the slit members 11 a to 11 d. The slit members 11a and 11b make a pair, and can move by the same amount in one direction (X direction) perpendicular to the optical axis around the optical axis of the laser beam. Further, the slit members 11c and 11d are paired and can move by the same amount in the direction (Y direction) perpendicular to the optical axis and the X direction around the optical axis of the laser light. Further, two electric motors (not shown) are provided, one electric motor controls the movement of the slit members 11a and 11b, and the other one electric motor moves the slit members 11c and 11d. Is to control. Thus, by independently controlling the two electric motors, the slit members 11a and 11b and the slit members 11c and 11d can be controlled independently of each other, and the shape of the opening 12 can be changed. , Can be square or rectangular of any size and aspect ratio.

  The variable slit portion 6 is irradiated with the laser beam 21c having the smallest beam diameter, and the laser beam 21c is passed through the opening 12 to shape the laser beam 21c into a desired repair shape and to have a spread angle. The laser beam 21d is emitted. Then, the laser light 21 d passes through the relay lens 7 and the objective lens 8 so that an image of the variable slit portion 6 is formed on the processed surface of the workpiece 50.

  Next, the operation of the laser CVD repair apparatus according to this embodiment configured as described above will be described. 4 is a diagram showing the optical axis vertical shape of the laser beam on the AA ′ plane shown in FIG. 1 and its intensity distribution, and FIG. 5 is the optical axis of the laser beam on the BB ′ plane shown in FIG. FIG. 6 is a diagram showing a vertical shape and its intensity distribution, and FIG. 6 shows the shape perpendicular to the optical axis of the laser beam and its intensity on the CC ′ plane shown in FIG. 1, that is, on the side of the regular pyramid prism 5 of the variable slit portion 6. FIG. 7 is a diagram showing the vertical shape of the optical axis of the laser beam on the DD ′ plane shown in FIG. 1, that is, the processed surface of the workpiece 50, and its intensity distribution. 4 to 7 show a case where laser light having a relatively long wavelength, for example, infrared laser light, is used as the laser light and the regular quadrangular pyramid prism 5 is not rotated.

  FIG. 8 is a diagram showing the shape perpendicular to the optical axis of the laser beam and its intensity distribution on the CC ′ plane shown in FIG. 1, that is, on the side of the regular pyramid prism 5 of the variable slit portion 6. FIG. 9 shows a case where a laser beam having a strong coherence and a short wavelength, for example, an ultraviolet laser beam is used and the regular quadrangular pyramid prism 5 is not rotated. FIG. 9 shows a CC ′ plane shown in FIG. 6 is a diagram showing the shape perpendicular to the optical axis of the laser beam on the side of the regular square pyramid prism 5 and its intensity distribution, and a laser beam having a high coherence and a short wavelength, such as an ultraviolet laser beam, is used as the laser beam. The case where the shape prism 5 is rotated is shown. 4 to 9 is the direction in which the slit members 11a and 11b move in the variable slit portion 6 shown in FIG. 3, and the Y direction is the slit in the variable slit portion 6 shown in FIG. This is the direction in which the members 11c and 11d move.

  First, in order to facilitate understanding, an operation when a laser beam having a relatively long wavelength, for example, an infrared laser beam is used as the laser beam and the regular quadrangular pyramid prism 5 is not rotated will be described. First, as shown in FIG. 1, the repair portion of the work 50 is disposed at the focal position of the objective lens 8. Then, the raw material gas supply means supplies the raw material gas for CVD to the repair portion. Further, by controlling the two electric motors of the variable slit portion 6, the slit members 11 a to 11 d are moved to adjust their positions, and the shape of the opening 12 is a shape corresponding to the repair shape of the workpiece 50. To do.

  In this state, the laser oscillator 2 oscillates the laser beam 21a by single mode laser oscillation. The laser beam 21a is incident on the beam expander 4 with a spread angle. Then, by passing through the beam expander 4, the spread angle of the laser beam 21 a is reduced by the reciprocal of the magnification of the beam expander 4, and the beam diameter is made parallel to that before entering the beam expander 4. In comparison, the magnification is multiplied by the multiplication factor of the beam expander 4, and the laser beam 21a becomes a collimated laser beam 21b.

  On the AA ′ plane, as shown in FIG. 4, the laser beam 21b after passing through the beam expander 4 has a circular shape perpendicular to the optical axis, and its intensity distribution is in a direction perpendicular to the optical axis. For example, in the X direction and the Y direction shown in FIG. 4, the Gaussian distribution is stronger at the center than at the periphery.

  Further, when the laser beam 21b passes through the regular quadrangular pyramid prism 5, the laser beam 21b is divided into four portions by the four roof-shaped surfaces 5a to 5d formed on the regular quadrangular pyramid prism 5, and each portion Is refracted in the diagonal direction of the regular quadrangular pyramid prism 5, and the peripheral portion where the intensity of the laser beam 21b is weak is refracted toward the central portion, and conversely, the central portion where the intensity of the laser beam 21b is strong is refracted toward the peripheral portion. The laser beam 21c is transmitted. The angle of refraction is determined by the inclination angles of the surfaces 5a to 5d of the regular quadrangular pyramid prism 5.

  At this time, on the BB ′ plane between the regular quadrangular pyramid prism 5 and the variable slit portion 6, as shown in FIG. 5, the optical axis vertical shape of the laser beam 21 c is square, and the intensity distribution is The peripheral part has a stronger distribution than the central part. In the variable slit portion 6, that is, the CC ′ plane, as shown in FIG. 6, the position corresponding to the center of the regular quadrangular pyramid prism 5 in one portion of the laser beam 21c divided into four is this portion. It coincides with the peripheral part of the part adjacent to. For this reason, the peripheral part where the intensity in the laser beam 21a is weak is concentrated in the central part in the CC ′ plane, and conversely, the central part in which the intensity in the laser beam 21a is strong is refracted in the peripheral part in the CC ′ plane. Thus, the intensity distribution is a rectangular distribution with a flat top portion, that is, a flat top type distribution. As a result, the shape perpendicular to the optical axis of the laser beam 21c remains square and its area is minimized, and the intensity distribution of the laser beam 21c is a uniform distribution in which the intensity at the center and the intensity at the periphery are equal to each other. .

  Then, the laser beam 21c passes through the opening 12 of the variable slit portion 6, so that the laser beam 21c is shaped into a repair shape and emitted as the laser beam 21d. The laser beam 21d is a laser beam having a repair shape in the optical axis vertical direction, a uniform intensity distribution, and a certain spread angle.

  This laser beam 21d becomes a laser beam 21e that is condensed by passing through the relay lens 7, and this laser beam 21e becomes a laser beam 21f that is further condensed by passing through the objective lens 8, so that the repair portion of the workpiece 50 is repaired. Is irradiated. At this time, the image of the opening 12 of the variable slit portion 6 is reduced and formed on the processing surface of the workpiece 50. The reduction magnification at this time is determined by the focal length of the relay lens 7, the focal length of the objective lens 8, and the distance between the variable slit portion 6, the relay lens 7 and the objective lens 8. As shown in FIG. 7, the optical axis vertical shape of the laser beam 21f on the processing surface of the workpiece 50 is a repair shape defined by the opening 12, and the intensity distribution is uniform.

  The above explanation is an operation when a laser beam having a relatively long wavelength, for example, an infrared laser beam is used as the laser beam and the regular quadrangular pyramid prism 5 is not rotated. Next, the regular quadrangular pyramid prism 5 is rotated. The operation when a laser beam having a relatively short wavelength and a strong coherence, for example, an ultraviolet laser beam is used as the laser beam will be described.

  As shown in FIG. 8, when laser light having a short wavelength or strong coherence is used as the laser light, each part divided into four by the regular quadrangular prism 5 after the laser light has passed through the regular quadrangular pyramid prism 5. Interfere with each other, and interference fringes with a constant pitch appear in the variable slit portion 6. This interference fringe also appears on the processed surface of the workpiece 50. For this reason, the uniformity of the intensity distribution of the laser beam is significantly reduced.

  In order to solve this problem, in this embodiment, the regular quadrangular pyramid prism 5 is rotated at a high speed. That is, the rotation drive motor 9 is driven to rotate the rotation shaft portion, and the rotation mechanism portion 10 transmits the rotation of the rotation shaft portion of the rotation drive motor 9 to the regular quadrangular pyramid prism 5, so that the regular quadrangular pyramid is transmitted. The shaped prism 5 is rotated around its central axis, that is, the optical axis of the laser beam 21b. As a result, as shown in FIG. 9, the disturbance of the intensity distribution due to the interference fringes is averaged and made uniform over time. The intensity distribution shown in FIG. 9 is obtained by averaging the intensity distribution of the laser light in the variable slit portion 6 over a time longer than the rotation period of the regular quadrangular pyramid prism 5. Thereby, the optical axis perpendicular | vertical shape of the laser beam in the variable slit part 6 becomes circular, and the intensity distribution is made uniform. Then, the laser light passes through the opening 12 of the variable slit portion 6 so that the peripheral portion is shielded and shaped into a repair shape. At this time, since the peripheral portion generated by the rotation is shielded by the variable slit portion 6, only the central portion where the intensity distribution of the laser light is more uniform can be used.

  As a result, the repaired portion of the workpiece 50 is irradiated with the laser beam 21f having a uniform intensity. On the other hand, since the CVD source gas is supplied to the repair portion by the source supply means, a desired film is formed by laser CVD and repair is performed. Thereby, favorable processing without processing unevenness can be performed.

  Next, the effect of this embodiment will be described. In the present embodiment, since the regular quadrangular pyramid prism 5 is rotated about its central axis by the rotation drive motor 9 and the rotation mechanism unit 10, the laser beam having a strong coherence as the laser beam or the wavelength is short. Even when laser light is used, unevenness in intensity distribution due to interference fringes can be eliminated, and uniform repair can be performed.

  Further, by interposing the regular quadrangular pyramid prism 5 in the optical path of the laser light, the intensity distribution can be made uniform even when the intensity distribution of the laser light emitted from the laser oscillator 2 is a Gaussian distribution. In addition, since the laser beam is homogenized using a regular quadrangular pyramid prism, the cost can be reduced compared to the case of using a beam shaping device such as a kaleidoscope or fly-eye type homogenizer. It can be kept low. Callide scopes and fly-eye homogenizers are extremely expensive, but using a regular quadrangular pyramid prism can reduce the cost of the device by a fraction to a few tens of times compared to using these beam shapers. 1 can be suppressed. Further, when a beam shaping device such as a kaleidoscope or fly-eye type homogenizer is used, the transmission loss of laser light is 30 to 70%, but when a regular quadrangular prism is used, the transmission loss of laser light is several percent. Can be suppressed. For this reason, the utilization efficiency of a laser beam improves.

  Furthermore, if the refractive index of the regular quadrangular pyramid prism 5 is set so that the distance between the regular quadrangular pyramid prism 5 and the variable slit portion 6 is increased, redundancy occurs at the position where the variable slit portion 6 can be arranged, It is not necessary to strictly position the variable slit portion 6 in the optical axis direction, and it is not necessary to strictly position the workpiece 50 in the optical axis direction, and the margins for the positions of the variable slit portion 6 and the workpiece 50 in the optical axis direction are eliminated. Can be secured. For this reason, the imaging optical device 3 can be easily assembled and the workability of the repair work can be improved.

  In the present embodiment, an example in which a regular quadrangular pyramid prism is used as the pyramid prism has been shown. However, the present invention is not limited to this, and for example, a triangular pyramid or a pentagonal pyramid or more polygonal pyramid prism is used. May be.

  Next, a second embodiment of the present invention will be described. Compared with the first embodiment described above, this embodiment is provided with an axion, which is a conical prism, instead of the regular quadrangular pyramid prism 5 (see FIG. 1). The conical prism is made to be a laser by the point that the central axis is slightly inclined with respect to the optical axis of the laser beam and the apex is arranged so that the laser beam passes, and the rotation drive motor and the rotation mechanism. The difference is that it rotates around the optical axis of light. Other configurations in the present embodiment are the same as those in the first embodiment.

  In this embodiment, the rotation drive motor and the rotation mechanism unit rotate the conical prism (axion) about the optical axis of the laser beam as the rotation axis. At this time, since the rotation axis is slightly inclined with respect to the central axis of the conical prism, the conical prism rotates with a slight eccentricity. Thereby, the interference fringes generated when the laser light passes through the conical prism can be averaged temporally, and the uniformity of the laser light due to the interference fringes can be smoothed. Operations and effects other than those described above in the present embodiment are the same as those in the first embodiment described above.

  In the present embodiment, an example in which an axion that is a conical prism is used as the conical prism has been described. However, the present invention is not limited to this, and a pyramid prism may be used, for example, a regular quadrangular pyramid. A shaped prism may be used.

  The present invention can be suitably used for, for example, an integrated circuit such as a pixel circuit of a semiconductor device and a liquid crystal display, and a laser CVD repair apparatus for repairing a photomask for manufacturing these integrated circuits.

It is an optical model figure which shows the laser CVD repair apparatus which concerns on the 1st Embodiment of this invention. It is the front view and side view which show the regular square pyramid prism shown in FIG. It is a perspective view which shows the variable slit part shown in FIG. It is a figure which shows the optical axis perpendicular | vertical shape of the laser beam in the A-A 'surface shown in FIG. 1, and its intensity distribution. It is a figure which shows the optical axis perpendicular | vertical shape of the laser beam in the B-B 'surface shown in FIG. 1, and its intensity distribution. It is a figure which shows the optical axis perpendicular | vertical shape of the laser beam in the C-C 'surface shown in FIG. 1, ie, the square pyramid prism 5 side of the variable slit part 6, and its intensity distribution. It is a figure which shows the optical axis perpendicular | vertical shape of the laser beam in the D-D 'surface shown in FIG. 1, ie, the processed surface of the workpiece | work 50, and its intensity distribution. It is a figure which shows the optical axis perpendicular | vertical shape of the laser beam in the CC 'surface shown in FIG. 1, ie, the regular tetragonal pyramid prism 5 side of the variable slit part 6, and its intensity distribution, and has a strong coherence property as a laser beam. Shows a case where a short laser beam, for example, an ultraviolet laser beam is used and the regular quadrangular pyramid prism 5 is not rotated. It is a figure which shows the optical axis perpendicular | vertical shape of the laser beam in the CC 'surface shown in FIG. 1, ie, the regular tetragonal pyramid prism 5 side of the variable slit part 6, and its intensity distribution, and has a strong coherence property as a laser beam. Is a case where a short laser beam, for example, an ultraviolet laser beam is used and the regular quadrangular pyramid prism 5 is rotated. (A) thru | or (d) is a figure which shows the optical apparatus of patent document 2, (a) is an optical model figure, (b) is the optical axis perpendicular | vertical of the laser beam before passing a quadrangular pyramid prism. FIG. 4C is a plan view of the quadrangular pyramid prism as viewed from the optical axis direction, and FIG. 4D is a diagram illustrating the shape perpendicular to the optical axis of the laser light applied to the workpiece.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1; Laser CVD repair apparatus 2; Laser oscillator 3; Imaging optical apparatus 4; Beam expander 5; Regular quadrangular pyramid prism 5a-5d; Surface 6; Variable slit part 7; Relay lens 8 for imaging 8; Rotation drive motor 10; Rotation mechanism 11a to 11d; Slit member 12; Opening 21a to 21f; Laser beam 50; Workpiece 101; Optical device 102; Square pyramid prism 103a, 103b; Laser beam 104; A line representing the intensity distribution of the laser beam 103a on the plane perpendicular to the optical axis 106; a line representing the intensity distribution of the laser beam 103b on the processed surface 104;

Claims (6)

In an imaging optical device that is incorporated in a laser repair device that repairs an object to be corrected by irradiating laser light, and that shapes the laser light into a repair shape and guides it to the object to be corrected, the central axis of the image forming optical device is the laser light A pyramid prism arranged so as to coincide with the optical axis of the laser beam, a slit for shaping the laser beam condensed by the pyramid prism into a repair shape, and an image of the slit formed on the object to be corrected An imaging optical apparatus comprising: an optical element for rotating; and a rotating means for rotating the pyramid prism about a central axis thereof. 2. The imaging optical device according to claim 1, wherein the pyramid prism is a regular quadrangular pyramid prism. In an imaging optical device that is incorporated in a laser repair device that repairs an object to be corrected by irradiating laser light, and that shapes the laser light into a repair shape and guides it to the object to be corrected, the central axis of the image forming optical device is the laser light A conical prism that is inclined with respect to the optical axis of the laser beam and arranged so that the laser beam passes through the apex thereof, a slit that shapes the laser beam condensed by the conical prism into a repair shape, An imaging optical apparatus comprising: an optical element that forms an image of a slit on the object to be corrected; and a rotating unit that rotates the cone-shaped prism about an optical axis of the laser light. The imaging optical device according to claim 3, wherein the conical prism is a conical prism. In a laser repair apparatus that repairs a correction target object by irradiating a laser beam, a laser oscillator and an imaging optical apparatus that shapes the laser light emitted from the laser oscillator into a repair shape and guides it to the correction target object And the imaging optical device is the imaging optical device according to any one of claims 1 to 4. 6. The laser repair according to claim 5, further comprising source gas supply means for supplying a CVD source gas to a position of the object to be corrected that is irradiated with the laser beam, and performing the repair by laser CVD. apparatus.

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