JP2002243914A - Lens correcting device, lens correcting method and lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a precision processing method optimum for accurately correcting the shape of an aspherical lens whose shape is complicated, and further to provide a highly accurate lens having excellent surface smoothness and complicated shape. SOLUTION: After specifying a characteristically defective spot of a lens, the surface shape is evaluated, shape correction amount is decided according to the condition of the surface shape, and the shape of the defective spot of the lens is corrected. Various methods are considered as a shape correction means, and the optimum shape correction means is selected according to the shape and the size of a defective part. The shape is corrected by filling a shape defective part 2 with optical material 3 when the defect of the surface shape of the lens 1 is based on the shape of a recessed part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens correcting device, a lens correcting method, and a lens for correcting a surface shape of a lens used for an optical product such as an image forming apparatus and a camera using an electrophotographic technique.

[0002]

2. Description of the Related Art Conventionally, the most common technique for correcting a lens is based on a polishing method. For example, JP 62
As described in JP-A-203744, a polishing plate is preliminarily processed into a shape having a reciprocal relationship with a lens shape to be processed, and the polishing plate is pressed against a glass material, and abrasive grains are formed on the polishing plate and the glass. This is a method in which the material is supplied to the gap between the materials and rubbed.

In this method, since polishing is performed using very fine abrasive grains, there is an advantage that a processing stress applied to a glass material during processing is small, and therefore, distortion remaining in a workpiece is small. However, since the processing cannot be performed unless the final finished shape of the workpiece is a simple shape, the degree of freedom in selecting the processing shape is small.

[0004] On the other hand, as the performance of the optical system is required to be higher, it is important to improve the accuracy of the lens shape and to make the lens shape aspherical. It is difficult to process an aspherical surface by the above-mentioned polishing method, and generally, an aspherical surface is formed by machining using NC control. At this stage, the lens processing surface is not a mirror surface enough to withstand use as a lens, has a shape error of about several μm, and a mark of a processing tool, that is, a processing mark remains on the processing surface.

By the way, if the ductile mode grinding is performed, it is possible to obtain a mirror-polished surface even with a brittle material such as glass. For example, according to the aspherical lens processing method described in Japanese Patent Application No. 2-53557, a workpiece is mounted on a table rotated by a motor, and a grindstone for processing the workpiece is mounted on an air spindle. 10,000 rp
It rotates at a rotational speed of about m.

Then, a pulse is detected from a rotary encoder directly connected to the rotary shaft of the rotary table, and processing data is supplied to the piezo actuator based on the pulse, and the linear table is continuously moved back and forth. Further, the air spindle is step-feeded every rotation of the rotary table to change its position, thereby changing the contact position between the grindstone and the workpiece.

According to this method, any non-axial symmetric, aspherical shape can be machined. In addition, this method
Since the cutting depth of the grindstone with respect to the workpiece can be controlled on the order of submicron, it is possible to grind brittle materials in ductile mode, and it is possible to obtain a mirror surface sufficient for use as a lens by grinding alone Becomes
Also, the shape error can be reduced to a size on the order of submicrons required for a lens. But,
This method has the following problems. (1) A great amount of processing time is required for finishing the aspherical portion. (2) Processing marks having irregularities on the order of submicron remain on the ground surface.

As a result, when high resolution of the lens is required, the slight processing trace has a bad influence on the optical characteristics of the lens. Therefore, when an optical element such as a lens is processed by NC processing, finishing processing is required. Generally, a polishing method is often used as a finishing method. In the case of finishing the aspheric surface by a polishing method, for example, the operation of rubbing diamond abrasive grains against the finished surface with a soft pad such as felt is repeated to adjust the state of the finished surface. The shape error component on the lens surface is roughly divided into 3
There are types. (1) Undulation (pitch: several hundred μm to several mm order) (2) Surface roughness (pitch: submicron to micron order) (3) Processing mark (pitch: several tens μm to several hundred μm order) Of these, the undulation component largely depends on the machine accuracy of the NC processing machine. Therefore, since it cannot be corrected by the finish polishing, it is necessary to reduce as much as possible in the pre-processing stage. On the other hand, the surface roughness can be sufficiently improved by finish polishing. However, the processing marks are located between the swell and the surface roughness, where the size of the pitch and the size of the irregularities are between the swell and the surface roughness. If correction is performed by polishing, the shape of the entire lens is damaged and the swell component is increased.

Further, since the machining trace is a trace of contact of the tool with the surface of the workpiece, it cannot be reduced at the time of pre-processing by the NC processing machine as in the case of reducing the waviness component. The amount of interference of the tool with the workpiece during machining,
That is, the size of the machining trace is reduced by reducing the cutting depth of the tool. However, even if the processing conditions slightly change, the cutting depth of the tool may fluctuate slightly, and a local shape defect such as a processing mark may remain on the lens surface.

[0010]

As described above, by using the NC processing, a complicated lens shape can be processed. However, as long as machining is performed, machining marks (local defective shape) always occur due to contact between the tool and the surface of the workpiece. Depending on the degree of the shape defect, the optical characteristics of the lens may be degraded. Further, some lenses, such as scanning lenses, cannot be used as non-defective products due to the presence of a defective portion in a part of the lens.

SUMMARY OF THE INVENTION An object of the present invention is to provide a lens correcting device, a lens correcting method, and a lens for efficiently correcting a lens with high accuracy by solving the above-mentioned drawbacks of the prior art.

[0012]

The gist of the present invention to achieve the above object is as follows. Identify the defective lens characteristics. For example, in the case of a scanning lens, light is scanned in the range of use of the lens, and the shape and the beam diameter of the condensed beam are measured to identify a portion where the condensing characteristic of the lens is defective. The lens surface shape at the position where the lens characteristics are defective is evaluated, and the shape correction amount is determined based on the state of the surface shape. Correct the shape of the defective lens. Various shape correcting means can be considered, and an optimum shape correcting means is selected according to the shape and size of the defective portion.

Next, an embodiment of the present invention will be described with reference to the drawings. 1A is a perspective view of the lens 1, FIG.
(B) is an enlarged view of the defective shape portion (concave portion) 2, and (c) is a cross-sectional view taken along the line AA 'of (b).

In the present invention, when the surface shape defect of the lens 1 is based on the concave shape as shown in FIG. 1A, the shape is corrected by filling an optical material 3 such as a polymer into the defective shape portion (recess) 2. I do. Since the defective shape portion (concave portion) 2 which causes the characteristic failure exists locally, the area ratio occupied by the defective shape portion is extremely small. Therefore, it is more reasonable to correct the shape by selectively filling such a defective shape portion (concave portion) 2 with the optical material 3.

As a method of correcting the shape by filling the concave portion 2 on the surface of the lens 1 with the optical material 3, there is the following method. That is, the shape is corrected by burying a material whose optical characteristics are very close to the lens material in the concave portion 2 which is a shape defect portion. Examples of the material to be embedded include an inorganic material such as SiO ₂ , an organic material such as a polymer, and a vitrified material.

For example, it is a polymer composed of Si, N, H (or an organic group), and silica (SiO
₂ ) A method of forming a SiO ₂ thin film layer in a concave portion by selectively applying and baking a glass conversion material such as polysilazane to be converted into a material, or selectively filling and curing a polymer material in a concave portion which is a defective shape portion. There is a method of correcting the shape by performing the correction.

Since the position of the defective shape is specified, the concave portion 2 can be selectively filled with the material by positioning the tool for discharging the filling material 3 at the defective shape of the lens 1. Becomes Alternatively, a photosensitive material is applied to the entire surface of the lens 1 as the filling material 3,
A method of irradiating a light having a specific wavelength to a defective shape portion and then removing unnecessary resin to selectively fill the concave portion 2 with a material can be considered.

Next, when a light-collecting characteristic defect occurs due to a locally existing convex shape, the shape is corrected by selectively removing the convex portion. As a means for shaving off the convex portion 2 ′ locally present on the surface of the lens 1, for example, a method using a mechanical polishing method is used. That is, as shown in FIG. 2, a method of locally polishing using a small polisher 4 in order to scrape off the convex portion 2 ′ located in a minute area is conceivable.

It is also conceivable to remove the projections 2 'by using a chemical vaporization method. That is, as shown in FIG. 3, while supplying a reactive gas (not shown) such as SF ₆ or CF ₄ around the convex portion 2 ′, the electrode 5 near the convex portion 2 ′ and the convex portion 2 ′ are supplied. Locally generates a plasma 6 to generate radicals (not shown) of a reactive gas, further reacts the radicals with the convex portions 2 ′, and volatilizes and removes reaction products to thereby form convex portions on the surface of the lens 1. It is possible to selectively remove the convex portion 2 ′ existing on the surface of the lens 1 by using plasma application processing for removing the portion 2 ′.

As a method capable of correcting the shape irrespective of the unevenness of the defective shape portion, there is a method by a shape transfer method. That is, as shown in FIG. 4, a small amount of a photosensitive polymer, for example, an ultraviolet curable resin 7 is dropped on the defective shape portion, and the resin 7 is molded and pressed by a mold 8 having a master shape of the lens 1, and ultraviolet rays (not shown) Irradiation and curing to form a film enable efficient shape correction.

Next, each embodiment will be specifically described. (Embodiment 1) FIG. 5 shows an asymmetrical aspherical fθ glass lens 1 used for shape correction in this embodiment. BK7 was used for the glass material of the lens 1. The overall length of the lens 1 is 130 mm and the width is 15 mm. The surface A side of the lens 1 has a radius of curvature R1 in the main scanning direction, and has radii of curvature r1, r2 in the sub-scanning direction.
It has a so-called deformed toric shape that differs depending on the location of r3, and the B surface is a planar shape.

Both surface A and surface B are mirror finished. A
Since the surface has an aspherical shape, it was processed by NC grinding. In this example, since the ductile mode grinding is performed, the surface is considerably mirror-finished only by the grinding processing. However, from the processing principle, the processing mark 9 of the grinding stone is in the main scanning direction of the lens 1 as shown in FIG. In the case of this embodiment, the average width of the processing marks 9 was about 100 μm, the average depth was 0.047 μm, and the average pitch was about 100 μm. The surface roughness was 0.019 μm in average surface roughness, and the undulation amount of one glass lens surface was 0.28 μm PP in a range of 8 mm in the sub-scanning direction.

Next, using the lens characteristic evaluation optical system shown in FIG. 7, the focusing characteristics of the lens 1 were examined. Light emitted from an optical system 10 including a light source is reflected by a mirror 11. The mirror 11 is mounted on the rotary stage 12 and can scan light. A light receiving sensor 13 is arranged at a position where the light passing through the lens 1 is just converged, and the shape and diameter of the condensed beam are measured by the light receiving sensor 13, and the result is displayed on a monitor 14.

The light receiving sensor 13 is mounted on a translation stage 15. Therefore, the light receiving sensor 13 can be moved even if the light condensing position changes by scanning with light, so that the condensed beam can be received at any position. As a result of evaluating the light-gathering characteristics of the lens 1 using this lens-characteristic evaluation optical system, disturbance of the light-gathering characteristics was recognized in a part of the lens surface. This was a position 40 mm from the lens end face (length direction).

In order to check the surface shape at this position,
The lens surface shape in the width direction was measured using a shape measuring device (not shown). As a result, a width 400 mm toward the center of the lens at a position 5.2 mm from the lens end surface (width direction).
It was found that there were scratches (recesses) 2 of μm, length of 1200 μm and depth of 0.13 μm.

Therefore, in order to correct the shape of the lens surface defective portion, as shown in FIG.
A micropipette 16 as a microliter is placed at the position of the scratch 2 on the surface of the lens 1, and a liquid glass conversion material 3 ′ is discharged toward the wound recess 2, whereby the concave portion 2 is formed.
Was filled with the glass conversion material 3 ′. Then, immediately put the lens 1 on a spin coater (not shown),
Spin at pm for 15 seconds to remove excess solution.

Polysilazane was used as the glass conversion material 3 '. Polysilazane is Si, N, H (or organic group)
Having a number average molecular weight Mn of 500 to 25.
It is a material that dissolves in an organic solvent such as xylene or dibutyl ether and is converted to silica (SiO ₂ ) by heating or the like. Silazane is a compound having a Si—N bond, and polysilazane is based on SiH ₂ NH. FIG. 18 is an explanatory view showing a state in which polysilazane is fired in the air to react with oxygen and moisture to be converted into dense, high-purity amorphous silica.

Next, after the material filled in the wound concave portion 2 was naturally dried, it was baked in an electric furnace 17 at 300 ° C. for 1 hour as shown in FIG. 8B to form an SiO ₂ layer. When the filled portion was analyzed, it was almost 100% pure quartz glass.

As a result of measuring the surface shape of the lens 1 after the shape correction, the depth of the flaw 2 was 0.13 μm before the correction, but was reduced to 0.07 μm after the correction. Also, the light-collecting characteristics were remarkably improved, and both the beam shape and the beam diameter returned to normal.

(Embodiment 2) One of the aspherical fθ glass lenses 1 manufactured by the same method as in Embodiment 1 having poor light-collecting characteristics is selected, and the shape is defective by the same method as in Embodiment 1. Locations were detected. As a result, in the length direction: 48 mm from the lens end face, and in the width direction: 6.1 mm from the lens end face, a width of 460 μm and a length of 6 mm toward the center of the lens.
There was a scratch 2 having a thickness of 20 μm and a depth of 0.24 μm. When the volume of the concave portion was calculated from the measured value of the flaw 2, the volume of the flaw 2 was about 68.5 picoliter.

Therefore, in order to correct the shape of the defective lens surface portion, as shown in FIG. 9A, an ink jet nozzle (micro nozzle) 18 having a discharge capacity of 60 picoliters per discharge is used to damage the lens surface. (Concave) 2 and fix 60 μl of the polysilazane solution in the recess 2.
And the concave portion 2 was filled with polysilazane 3 ′.

Since the amount of the filling material is extremely small, natural drying is completed in about 1 minute, and the resultant is baked in an electric furnace 17 at 350 ° C. for 1 hour to form a SiO ₂ thin film 3 ″ [FIG. b)].

As a result of measuring the lens surface shape after the shape correction, the depth of the flaw 2 was 0.24 μm before the correction, but was reduced to 0.05 μm after the correction. Also, the light-collecting characteristics were remarkably improved, and both the beam shape and the beam diameter returned to normal.

Example 3 In the same manner as in Example 1, an aspherical Fθ glass lens 1 having a poor light-collecting characteristic was selected, and a shape-defective portion was detected. As a result, the length direction: 2 from the lens end face
6 mm, width direction: 320 μm in width and 2300 μ in length toward the center of the lens at a position 4.8 mm from the lens end face
m and a scratch 2 having a depth of 0.18 μm.

Therefore, the lens surface shape is modified.
Was. The procedure is as follows. As shown in FIG.
Thus, a photosensitive lens having a negative photosensitive characteristic is provided on the surface of the lens 1.
Lysilazane 3 'was applied by spin coating. Exposure
Polysilazane 3 'is SiO _Two Precursor for firing the layer
Photocatalyst added to obtain photosensitivity
Liquid compound with a basic structure of-(SiH_Two NH)-
Inorganic polymer. The coating film thickness was 2
0.18 μm, which is the same as the depth of

At 90 ° C., the lens 1 having the coated thin film
After primary baking for an hour, as shown in FIG.
9 was condensed so as to have a beam diameter of 300 μm, and was selectively irradiated to the flaw 2 on the surface of the lens 1 to perform selective exposure. After washing the lens 1 with pure water, development is performed using a developer. The lens 1 is secondarily fired at 300 ° C. for one hour. As a result, the polysilazane thin film layer is converted into the SiO ₂ layer 3 ″. That is, the flaw 2 is filled with the SiO ₂ layer 3 ″ having a thickness of 0.18 μm (see FIG. 10C).

As a result of measuring the lens surface shape after the shape correction, the depth of the flaw 2 was 0.18 μm before the correction, but was reduced to 0.02 μm after the correction. Also, the light-collecting characteristics were remarkably improved, and both the beam shape and the beam diameter returned to normal.

(Embodiment 4) Length direction: 8 from lens end face
3 mm, width direction: 240 μm in width and 1800 μ in length toward the center of the lens at a position of 3.6 mm from the lens end face
The shape of the aspherical fθ glass lens 1 having a m and a flaw of 0.25 μm in depth was corrected. The procedure is as follows.

As shown in FIG. 11A, a photosensitive polysilazane 3 'having a negative photosensitive property was discharged onto the flaw 2 by using the micro nozzle 18 used in Example 2 on the surface of the lens 1. Since the volume of wound 2 is 108 picoliters,
The discharge was performed twice consecutively, and only the concave portion 2 was selectively filled with the polysilazane solution 3 ′ in a total of 120 picoliters.
The lens 1 on which the coated thin film is formed is primarily baked at 90 ° C. for 1 hour.

Next, as shown in FIG.
Was irradiated onto the entire surface of the lens 1 to perform exposure. Lens 1
At 300 ° C. for 1 hour. Thereby, the polysilazane thin film layer is converted into the SiO ₂ layer 3 ″ (FIG. 11 (c)).
reference〕.

As a result of measuring the surface shape of the lens after the shape correction, the depth of the flaw 2 was 0.25 μm before the correction, but was reduced to 0.03 μm after the correction. Also, the light-collecting characteristics were remarkably improved, and both the beam shape and the beam diameter returned to normal.

(Embodiment 5) Length direction: 6 from lens end face
5 mm, width direction: width 480 μm, length 450 μ toward the center of the lens at a position 6.6 mm from the lens end surface
The shape of the aspherical fθ glass lens 1 having the scratches 2 having a depth m of 0.15 μm was corrected. The procedure is as follows.

An acrylic ultraviolet curing resin 7 was used as a filling material. The UV curable resin 7 adjusts its refractive index, and BK7 (a refractive index of 1.51
63) A resin having almost the same value as that of the resin was used.

As shown in FIG. 12A, the above-mentioned ultraviolet curable resin 7 was applied to the surface of the lens 1 by spin coating. The coating thickness is 0.15 μm, which is the same as the depth of the scratch 2.
m. Next, as shown in FIG.
9 ′ was condensed so as to have a beam diameter of 500 μm, and was irradiated only to the flaw 2 on the lens surface to locally cure the resin.

The uncured resin adhering to the surface of the lens 1 is removed with isopropyl alcohol, and the surface of the lens 1 is further cleaned. The flaw 2 is filled with an acrylic resin layer 7 ′ having a thickness of 0.15 μm (see FIG. 12C).

As a result of measuring the lens surface shape after the shape correction, the depth of the flaw 2 was 0.15 μm before the correction, but was reduced to 0.01 μm after the correction. Also, the light-collecting characteristics were remarkably improved, and both the beam shape and the beam diameter returned to normal.

(Embodiment 6) Length direction: 7 from lens end face
2 mm, width direction: 320 μm in width and 540 μ in length toward the center of the lens at a position of 4.6 mm from the lens end surface
The shape of the aspherical fθ glass lens 1 having a m and a flaw of 0.37 μm in depth was corrected. The procedure is as follows.

As shown in FIG. 13A, since the volume of the flaw 2 was 64 picoliters, 60 picoliters of the ultraviolet curable resin 7 was discharged and filled into the lens flaw 2 using the micro nozzle 18. Thereafter, as shown in FIG. 13B, ultraviolet rays 19 ′ were irradiated on the entire surface of the lens 1 to perform curing.

As a result of measuring the lens surface shape after the shape correction, the depth of the flaw 2 was 0.37 μm before the correction, but was reduced to 0.02 μm after the correction. Also, the light-collecting characteristics were remarkably improved, and both the beam shape and the beam diameter returned to normal.

(Embodiment 7) Length direction: 6 from lens end face
4 mm, width direction: 140 μm in width and 820 μ in length toward the center of the lens at a position of 7.2 mm from the lens end face
m, aspherical surface f having a convex flaw 2 ′ having a height of 0.17 μm
The shape of the θ glass lens 1 was modified.

The shape is corrected as shown in FIG.
The polishing was performed by selectively polishing the convex scratches 2 'using cerium oxide as free abrasive grains using a felt polisher 4 of m. 600r rotation speed of polisher
pm, and after polishing for 5 minutes, the surface shape was measured. The height of the projections was 0.17 μm to 0.1 μm.
It was reduced to 07 μm. Also, the light-collecting characteristics were remarkably improved, and both the beam shape and the beam diameter returned to normal.

(Embodiment 8) Length direction: 8 from lens end face
3 mm, width direction: 540 μm in width and 1,730 μm in length toward the center of the lens at a position of 7.4 mm from the lens end surface
m, aspherical surface f having a convex flaw 2 ′ having a height of 0.23 μm
The shape of the θ glass lens 1 was modified. Fig. 1
As shown in FIG. 5, a chemical vaporization method using plasma 6 was applied.

That is, the positions of the processing electrode 5 and the lens surface convex flaw 2 ′ are controlled so that the convex portion 2 ′ of the processed surface is selectively processed so that the processed surface becomes flat. By locally generating a plasma state while supplying a reactive gas such as SF ₆ or CF ₄ to the periphery of the workpiece, radicals of the reactive gas are generated, and further, the workpiece reacts with the radical, thereby causing a reaction. By removing the product by volatilization, the convex portion 2 ′ on the surface of the workpiece was removed.

As a result, the height of the projection on the processed surface was 0.23 μm.
m to 0.06 μm. In addition, the light-collecting characteristics were significantly improved, and both the beam shape and the beam diameter returned to normal.

(Embodiment 9) Length direction: 6 from lens end face
3 mm, width direction: 1360 μm in width and 2280 in length toward the center of the lens at a position of 6.5 mm from the lens end face
The shape of the aspherical fθ glass lens 1 having irregularities of 0.27 μm in PV value over the range of μm was corrected. The specific method is as follows.

The shape correction was performed by transferring the shape of the mold surface having the master shape of the lens 1 to the lens surface with the ultraviolet curing resin 7 interposed. The volume of the correction location is about 840 picoliters. Therefore, FIG.
As shown in (b), a micro-nozzle 18 for discharging the ultraviolet curing resin 7 is positioned at the shape correcting section, and ultraviolet curing is performed at a pitch of 400 μm in five locations in the length direction and three locations in the width direction, a total of 15 locations. The droplet of the resin 7 is discharged.

Next, as shown in FIG.
A mold 8 having a master shape is superimposed thereon, and the ultraviolet curable resin 7 at the lens surface correction location is spread with the mold 8. Then, as shown in FIG. 17B, the lens 1 is irradiated with ultraviolet rays 19 ′ for 20 seconds to cure the resin, and the lens 1 is removed from the mold 8 (see FIG. 17C).

By performing the above operations, the mold surface shape is transferred to the surface of the ultraviolet curable resin layer on the lens 1, and the lens shape correction is completed. As a result of evaluating the surface shape of the corrected portion, the PV value of the unevenness was reduced to 0.06 μm. In addition, the light-collecting characteristics were significantly improved, and both the beam shape and the beam diameter returned to normal.

[0058]

As described above, the use of the method according to the present invention makes it possible to easily and efficiently reduce processing traces generated when machining the lens surface. as a result,
It has a feature that a lens having a complicated shape and requiring high accuracy can be easily processed in a short time.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram (recess filling) of a lens shape correcting method according to the present invention.

FIG. 2 is a conceptual view (projection removal) of a lens shape correction method according to the present invention.

FIG. 3 is a conceptual diagram of a lens shape correcting method by a chemical vaporization method according to the present invention.

FIG. 4 is a conceptual diagram of a lens shape correction method using a shape transfer method according to the present invention.

FIG. 5 is a perspective view of an off-axis symmetric aspherical fθ glass lens.

FIG. 6 is a perspective view showing a processing mark of an off-axis symmetric aspherical fθ glass lens.

FIG. 7 is a plan view of an optical system for evaluating lens light-collecting characteristics.

FIG. 8 is a schematic view of a method for correcting a lens shape by filling a glass conversion material.

FIG. 9 is a schematic view of a method for correcting a lens shape by filling a small amount of glass conversion material.

FIG. 10 is a schematic view of a method of correcting a lens shape by filling a photosensitive glass conversion material.

FIG. 11 is a schematic view of a method for correcting a lens shape by filling a small amount of a photosensitive glass conversion material.

FIG. 12 is a schematic view of a method of correcting a lens shape by filling an ultraviolet curable resin.

FIG. 13 is a schematic view of a method of correcting a lens shape by filling a small amount of an ultraviolet curable resin.

FIG. 14 is a schematic view of a lens shape correcting method by micro-polishing.

FIG. 15 is a schematic diagram of a lens shape correction method by a chemical vaporization method.

FIG. 16 is a schematic diagram of a lens shape correcting method by a shape transfer method.

FIG. 17 is a schematic view of a lens shape correcting method by a shape transfer method.

FIG. 18 is an explanatory view showing how polysilazane is converted to silica.

[Explanation of symbols]

Reference Signs List 1 lens 2 defective shape part (concave part, groove, groove part, scratch) 2 ′ defective shape part (convex part, scratch) 3 filling material (optical material) 3 ′ glass conversion material 3 ″ SiO ₂ thin film 4 polisher 5 electrode 6 plasma 7 UV curing resin 7 'Film forming unit 8 Master mold for shape transfer 9 Processing mark 10 Optical system including light source 11 Mirror 12 Rotary stage 13 Light receiving sensor 14 Monitor 15 Linear motion stage 16 Micropipette 17 Electric furnace 18 Inkjet nozzle (micro nozzle) 19 light (i-line) 19 'light (ultraviolet)

Claims (27)

[Claims] 1. A device comprising a defective portion specifying means for specifying a defective portion of a lens characteristic, a surface shape measuring means for measuring a surface shape of the defective portion, and a correction processing means for correcting the surface shape of the defective shape portion. A lens correction device characterized by the above-mentioned. 2. The lens repairing device according to claim 1, wherein the repair processing means is configured such that, when a concave portion is dominant as a cause of the defective shape in a lens surface unevenness state related to the defective lens shape, the fine processing portion is provided with the fine concave portion. A lens correction device characterized in that the concave portion is filled with a material having the same or very close optical characteristics to the lens material to correct the shape of the minute concave portion. 3. The lens correcting device according to claim 2, further comprising a calculating unit for measuring a surface shape of the defective lens portion and calculating a volume of a minute concave portion of the defective lens portion, and wherein the correction processing device includes the minute processing portion. A lens correction device, characterized in that a filling material having a volume equivalent to the volume of a concave portion is filled in a minute concave portion and the shape is corrected. 4. A lens correcting apparatus according to claim 2, wherein said correction processing means focuses and irradiates light on a shape correction portion of a lens surface on which a photosensitive material is applied in advance on the entire surface. A lens correction device characterized in that the material is filled and left only in the shape correction portion. 5. The lens repairing device according to claim 3, wherein a photosensitive material is used as the filling material, and light irradiating means for sensitizing the photosensitive material is provided. 6. The lens correction device according to claim 1, wherein the correction processing means is configured such that, in a lens surface unevenness state related to a lens shape defect, when a minute convex portion is dominant as a cause of the shape defect, A lens correcting device characterized in that it is configured to correct the shape of a minute convex portion by removing the minute convex portion. 7. The lens correction device according to claim 6, wherein the correction processing means includes a fine polisher,
A lens correction device, wherein a lens shape is corrected by removing minute projections existing in a lens surface shape defective portion using loose abrasive grains. 8. The lens correcting apparatus according to claim 1, wherein said correcting means has a removing means, and selectively removes a minute convex portion existing in the defective lens surface shape as said removing means. Means for controlling the position of the processing electrode and the micro-projection, and means for supplying a reactive gas around the micro-projection for locally generating a plasma state between the processing electrode and the micro-projection A lens correction device characterized in that the lens shape is modified by generating radicals of a reactive gas, further reacting the radicals with the minute projections, and volatilizing and removing the reaction product. 9. The lens correcting apparatus according to claim 1, further comprising: means for measuring a surface shape of the defective lens portion, calculating a volume of the minute uneven portion of the defective lens portion, and wherein the correction processing means has the volume A means for filling the fine irregularities with a photosensitive filler material that has a slightly larger volume than that of the master, and a female mold with the master shape of the lens superimposed on the lens surface to create a master shape A lens correction device configured to correct the lens shape by irradiating light and forming a film after transferring. 10. A lens correcting method comprising: a step of specifying a lens characteristic defective portion; a step of measuring a surface shape of the defective portion; and a step of correcting and processing the surface shape of the defective portion. 11. The lens correcting method according to claim 10, wherein in a state of irregularities on the lens surface related to the lens shape defect, when the minute concave portion is dominant as a cause of the shape defect, the optical characteristic of the minute concave portion is changed to the lens. A lens correction method, comprising a step of filling a material that is the same as or very close to the material and correcting the shape of the minute concave portion. 12. The lens correcting method according to claim 11, wherein the surface shape of the defective lens portion is measured to calculate the volume of the minute concave portion of the defective portion, and the filling has a volume equivalent to the minute concave portion volume. Filling a minute concave portion with a material and correcting the shape. 13. A method according to claim 11, wherein a filling material having photosensitivity is previously applied to the entire surface of the lens, and light is condensed and radiated only to the shape-corrected portion of the lens surface. A method of correcting the shape by performing development and cleaning so that the filler material remains in the shape-corrected portion. 14. A lens correcting method according to claim 12, wherein a photosensitive material is used as said filling material, and after the material is filled, the surface of the lens is irradiated with light to form a film, thereby correcting the shape. Lens correction method. 15. The lens correcting method according to claim 10, wherein, in the case of a lens surface irregularity related to a lens shape defect, when a minute convex portion is dominant as a cause of the shape defect, the minute convex portion is removed. A method of correcting the shape of the minute convex portion by performing the following. 16. A lens correcting method according to claim 15, further comprising a fine polisher, and removing the minute convex portion present in the lens surface shape defective portion using free abrasive grains, thereby correcting the lens shape. A lens correction method characterized by the above-mentioned. 17. The lens correcting method according to claim 15, wherein the position of the processing electrode and the position of the minute convex portion for selectively removing the minute convex portion present in the defective portion of the lens surface shape is controlled as the removing method. Then, while supplying a reactive gas such as SF6 around the minute convex portion, a plasma state is locally generated between the processing electrode and the minute convex portion to generate radicals of the reactive gas. A lens correcting method, comprising: correcting a lens shape by reacting a part with a radical to volatilize and remove a reaction product. 18. The lens correcting method according to claim 10, wherein the step of measuring the surface shape of the defective lens portion and calculating the volume of the minute uneven portion of the defective portion has a volume slightly larger than the volume. Irradiating light after transferring the master shape to the surface of the material filled in the minute unevenness by superimposing a female mold having the master shape of the lens on the surface of the lens by filling the photosensitive unevenness material into the minute unevenness; And correcting the lens shape by forming a film. 19. A lens obtained by specifying a lens characteristic defective portion, measuring the surface shape of the defective portion, and correcting the surface shape of the defective shape portion. 20. The lens according to claim 19, wherein in the unevenness of the lens surface related to the lens characteristic defect, when the minute concave portion is dominant as a cause of the shape defect, the optical characteristic of the minute concave portion is different from the lens material. A lens obtained by filling the same or very similar material and correcting the shape of the minute concave portion. 21. The lens according to claim 20, wherein the surface shape of the defective portion is measured, and the volume of the minute concave portion of the defective portion is calculated. A lens characterized by being filled in a concave portion and modified in shape. 22. The lens according to claim 20, wherein a photosensitive filling material is previously applied to the entire surface of the lens, and light is focused and irradiated only on the shape-corrected portion of the lens surface, and then developed. And a lens obtained by subjecting the filling material to the shape-corrected portion by performing cleaning to correct the shape. 23. The lens according to claim 21, wherein a photosensitive material is used as a filling material, and after filling the material, the lens surface is irradiated with light to form a film, and the shape is corrected. . 24. The lens according to claim 19, wherein, in a state of irregularities on the lens surface related to the lens shape defect, when the minute convex portion is dominant as a cause of the shape defect, the minute convex portion is subjected to removal processing. A lens characterized in that the shape of the minute convex portion is corrected by the above. 25. The lens according to claim 24, wherein a polishing process is performed using a fine polisher and free abrasive grains, thereby removing a minute convex portion present in the defective portion of the lens surface shape to correct the lens shape. A lens characterized by being applied. 26. The lens according to claim 24, wherein a position of a processing electrode and a position of the minute convex portion for selectively removing the minute convex portion present in the lens surface shape defect portion is controlled,
While supplying a reactive gas around the microprojections, a plasma state is locally generated between the processing electrode and the microprojections to generate radicals of the reactive gas and further react the radicals with the microprojections. And correcting the lens shape by volatilizing and removing the reaction product. 27. The lens according to claim 19, wherein the surface shape of the defective lens portion is measured, the volume of the minute uneven portion of the defective portion is calculated, and the lens has a slightly larger volume than the minute uneven portion volume. After filling the fine irregularities with the photosensitive filler material, the master shape is transferred to the surface of the material filled into the minute irregularities by superimposing a female mold having the master shape of the lens on the lens surface, and then irradiating light. A lens characterized by modifying the lens shape by forming a film.