JP4877640B2 - Manufacturing method of molding die for optical element, molding die for optical element, and optical element - Google Patents

Description

  The present invention relates to a manufacturing method for manufacturing a molding die for optical elements capable of shortening the molding cycle, a molding die for optical elements manufactured by the manufacturing method, and an optical element molded by the molding die for optical elements. About.

  According to a conventional method for producing a mold for plastic optical elements, a blank (primary processed product) is made of an Fe-based material such as steel or stainless steel, and no blank is formed on the blank. By chemical plating called electrolytic nickel plating, an amorphous nickel-phosphorus alloy is coated to a thickness of about 100 μm, and this plating layer is cut with a diamond tool by an ultra-precision processing machine, and the optical surface of the optical element is formed. A highly accurate optical surface transfer surface for molding was obtained.

  By the way, in recent years, an optical element has been developed in which a fine structure having a height of about several μm is provided on the optical surface of the optical element to give a function such as a diffraction effect. The fine structure of the optical surface of the optical element is obtained by forming in advance a fine structure corresponding to the molding transfer surface of the molding die and transferring the molding transfer surface to the optical element material by molding. Here, in order to obtain an optical element having desired optical characteristics by accurately transferring and molding the fine structure by, for example, injection molding or the like, it is necessary that the optical element material enters into the depth of the fine structure. However, in order to prevent the optical element material from sticking to the mold, the mold temperature is generally lower than the temperature of the optical element material. Therefore, the optical element material in contact with the microstructure of the mold Sometimes the surface cools and the viscosity increases, making it difficult to penetrate deep into the microstructure. Therefore, in order to allow the optical element material to enter the depth of the fine structure, the molding time is required to be 1.5 times longer than that in the case of molding the optical element without the fine structure. In this case, the number of optical elements produced per unit time is reduced, and there is a problem that the cost of the optical elements is increased.

On the other hand, by forming the mold from a material with high heat insulation such as ceramics, even if the optical element material touches, the heat conduction is suppressed and the fluidity is increased, and the optical element can be quickly reached to the depth of the fine structure. It can also make it easier for the material to enter.
Mitsubishi Engineering Plastics Co., Ltd. “Examination of transferability using ceramic heat insulating mold”, [online], June 2002, [searched July 16, 2004], Internet <URL; http: //www.enplanet .com / Company / 00000006 / Ja / Data / p019.html> JP 2002-96335 A

  However, according to such a conventional technique, plating is formed on the surface of the ceramic, and a fine structure is formed on the plating film by machining. However, the machining process and chemical plating process are mixed in the manufacturing process, and it takes a long time for delivery. The plating process is not always stable. The adhesion strength of the plating layer varies depending on the composition of the blank and the degree of contamination. Pinhole-like defects called pits occur, and the optical surface transfer surface must be created within the thickness of the plating layer. Therefore, when reworking the optical surface transfer surface, there is a margin in the plating thickness. There were problems such as the fact that it could not be processed. Moreover, there is a problem that the affinity between the plating and the ceramic is relatively low, and there is a risk of peeling off after long-term use. In particular, peeling is likely to occur due to the pressing force applied during optical element molding.

  The present invention has been made in view of such problems of the prior art, and can produce a molding die for an optical element that can reduce molding cycle time while having durability, and can mold an optical element with high accuracy. It is an object of the present invention to provide a method, a molding die for optical elements produced thereby, and an optical element molded thereby.

The method for producing a molding die for optical elements according to claim 1 is characterized in that the surface roughness of a die base material formed from a ceramic material having a thermal conductivity of 1 to 20 W / mK is Ra = 0.10000. After adjusting to the range of 50 μm, at least one of Pt, Ir, Au, Pd, Ru, Rh, Fe, Co, Ni, Zr, Al, Ti, Cu, W, Mo, Cr, B, P is formed on the surface. An amorphous metal film layer having a supercooled liquid region containing 20 to 80 mol% or more of any one or more elements is formed, and the mold optical surface (molding) is performed on the surface of the film layer. A surface on which the optical surface of the optical element to be transferred is formed).

  For example, when electroless Ni plating is attached to the surface of a mold base and a mold optical surface is formed there, a very long time of several weeks is required to obtain the required plating film thickness. It took considerable effort to form one mold.

  On the other hand, when an amorphous metal film layer having a supercooled liquid region is formed on a mold base as in the present invention, for example, from the material spaced from the mold base, the material A film layer can be formed by a film forming process (particularly sputtering, vapor deposition, etc.) in which particles are scattered and an amorphous alloy having a supercooled liquid region is deposited, thereby forming a film in a very short time. Therefore, as compared with the plating method, the manufacturing time of the optical element molding die (also simply referred to as a die) can be greatly shortened.

Furthermore, before a case of using the ceramics as Kikin type substrate, since ceramic is a high hardness hard to process materials, it is difficult to finish the mold optical surfaces having a microstructure by machining directly, thus the mold base A film layer with good machinability is formed on the mold optical surface. However, the electroless nickel plating (ENP film) film layer used as the mold optical surface material of the conventional molding die for optical elements has poor compatibility with ceramics and the like, and the adhesion between the mold substrate and the film layer is poor. There is a problem that is bad. On the other hand, in the present invention, since the amorphous metal film layer having the supercooled liquid region is formed on the mold base, the film can be formed in a short delivery time, and compared with the plating base By using an amorphous metal film layer with a supercooled liquid region that has a strong adhesiveness against cutting and a machinability equivalent to or better than that of an ENP film, the mold optical surface has a fine structure. In addition, it is possible to provide a molding die for optical elements with a heat insulating effect in a short delivery time. Further, by roughening the surface of the mold base within a range of Ra = 0.0.10 to 50 μm, the mold base made of a ceramic material, the amorphous metal film layer having the supercooled liquid region, It is possible to reinforce the adhesion.

  Further, in the present invention, by using an amorphous metal film layer having a supercooled liquid region as a mold optical surface material of a molding die for optical elements, a very small smooth optical film is formed by diamond cutting after film formation. A transfer surface can be easily created. In particular, when cutting fine structures such as diffractive grooves and DOE grooves with high accuracy and a large amount, breakage of fine tool edges is prevented by the high machinability of amorphous metal having a supercooled liquid region, and ， Because the tool wear is very little, it is possible to cut while maintaining the shape of the groove edge, which is important for maintaining the diffraction effect.

In addition, in the present invention, since a mold base formed of a ceramic material having a thermal conductivity of 1 to 20 W / mK is used, the optical element molding die itself can have a heat insulating effect. . Ceramic materials generally have a large specific heat and a high heat retention effect, so that the heat insulation effect of the mold can be enhanced. For example, when producing optical elements by molding, the upper and lower mold assembly process, molten resin injection process, mold pressure holding process, cooling (resin solidification) process, and optical element release process are repeated as one cycle. In addition, the temperature of the molding chamber and the mold fluctuates periodically. If this periodic fluctuation of temperature is large, it is necessary to wait until the mold temperature is stabilized. Especially when trying to transfer a fine structure (blazed shape, etc.) to the optical element, the cycle time is long. As a result, there is a problem that the optical element production capacity does not increase. On the other hand, according to the present invention, it is possible to shorten the time until the mold temperature is stabilized and shorten the cycle time by giving the mold a heat insulation effect and suppressing the fluctuation of the mold temperature in one cycle. it can. The lower the thermal conductivity, the higher the heat insulation effect of the mold. On the other hand, if the thermal conductivity is too low, it takes time to change the mold temperature, and the mold surface temperature has uneven temperature. Since it becomes easy to generate | occur | produce, it is preferable to select the material which has the heat conductivity of the range of 1-20 W / mK.

In particular, according to the present invention, by using a ceramic material having a thermal conductivity of 1 to 20 W / mK for the mold base, escape of heat from the optical element can be minimized when the optical element is molded. In the case of a mold base material using a conventional Fe-based material, since the thermal conductivity is about 50 to 90 W / mK, heat easily escapes from the optical element material, and it takes time to form a fine structure. However, according to the present invention, since the temperature of the optical element material can be kept high for a longer time than a mold base material using an Fe-based material, the mold can be formed with a low viscosity of the optical element material. Since it is pressed, the optical element material reaches the depth of the fine structure, and the molding transferability is improved.

  That is, in the present invention, an amorphous metal having a supercooled liquid region, which is very suitable for creating a fine-structured cutting process, is used as a mold optical surface material, and an optical element molding transferability is applied to a mold base. High performance optical elements with a fine structure on the optical surface can be molded with high precision and high efficiency by using in combination with mold materials with excellent thermal conductivity and low thermal conductivity. It becomes possible.

  Here, by including noble metal elements such as Pt, Ir, Au, Pd, Ru, and Rh in the amorphous metal film layer having the supercooled liquid region, it is possible to prevent oxidation and fusion with the resin. effective. Further, by including transition elements of Fe, Co, Ni, Ti, W, Mo, and Cr, the hardness of the film layer can be increased and the heat resistance temperature of the amorphous metal film layer can be increased. By mixing materials with good machinability such as Al and Cu, the machinability of the amorphous metal film layer can be further improved. By mixing B and P, the stabilization of the supercooled liquid region of the amorphous metal film layer can be improved.

  According to a second aspect of the present invention, there is provided a method for manufacturing an optical element molding die according to the first aspect, wherein the optical element molding die is used for molding an optical element having a diameter of 5 mm or less. Features.

  In particular, when an optical element having a diameter of 5 mm or less is molded, since the heat capacity of the element itself is small, the effect obtained by giving the mold a heat insulating effect is increased. In order to give a sufficient heat insulation effect to the mold in this way, use a material with low thermal conductivity (20 W / mK) for the mold base, use a material with a large specific heat, increase the mold shape. There are measures such as increasing the heat capacity of the mold. By providing the mold with sufficient heat insulation effect, it is possible to prevent severe fluctuations in the mold temperature during the molding cycle and a significant decrease in the mold temperature, and the thermal responsiveness to disturbances becomes dull. As a result, it is possible to obtain the molding transfer performance of the optical element fine structure equal to or higher than that of the mold using the Fe-based material despite the shorter molding cycle time.

  The method for producing a molding die for an optical element according to claim 3 is the invention according to claim 1 or 2, wherein the thickness of the film layer of the amorphous metal formed on the surface of the die substrate is used. Is characterized in that it has a thickness of 10 to 500 μm, so that a fine structure required for an optical element can be formed by, for example, diamond processing.

  When the thickness of the amorphous metal film layer is less than 10 μm, when the mold optical surface is formed by cutting or grinding, the thickness of the film layer to be cut by one cutting or grinding process is 1 to 5 μm. For this reason, the number of times that cutting or grinding can be performed is extremely limited, and the shape of the mold optical surface to be obtained must be created by almost one processing, which increases the processing difficulty. Further, since the film thickness variation of the film layer at the time of film formation is ± 5 μm or more, it can be said that it is practically difficult to process when the film layer thickness is 10 μm or less. On the other hand, the greater the thickness of the film layer, the greater the number of times it can be processed and the burden on the processing process. However, when the amorphous metal film layer having a thickness of 500 μm or more is formed, the stress of the film layer is increased. There is a risk of peeling from the mold base. Therefore, the thickness of the amorphous metal film layer is preferably in the range of 10 to 500 μm.

  However, the machining process of the mold optical surface is not limited to machining such as cutting and grinding. Taking advantage of the ease of transfer of the amorphous metal film layer with the supercooled liquid region, for example, by making a master mold with a fine structure and copying it from the master mold by molding transfer method, according to the ring shape of the optical element etc. It is also possible to form a fine structure on the mold optical surface (see Japanese Patent Application Laid-Open Nos. 2003-154529 and 2003-160343). According to this method, if one master mold is prepared, it is possible to easily produce molds by transferring the surface shape, eliminating the need to create mold optical surfaces one by one by machining. , The mold production period can be greatly shortened.

  According to a fourth aspect of the present invention, there is provided a method for producing a molding die for an optical element according to any one of the first to third aspects, wherein the amorphous metal having the supercooled liquid region has a thermal conductivity of 1 to 20 W. Therefore, the amorphous metal film layer having the supercooled liquid region can have a heat insulating effect, and the heat insulating effect of the entire mold can be improved.

According to a fifth aspect of the present invention, there is provided a method for producing a molding die for an optical element according to any one of the first to fourth aspects, wherein the mold base is zirconia, alumina, macor, macerite [Al ₂ O ₃ · wherein the _{K 2 O · B 2 O 3} · F] is formed from one of ceramics. Alumina, zirconia, macor, and macerite are all ceramics and have a thermal conductivity in the range of 1 to 20 W / mK, and heat is not easily transmitted, and therefore has a high heat insulating effect.

In the method for producing a molding die for optical elements of the present invention, the amorphous metal film layer having the supercooled liquid region may be formed by PVD treatment. When the amorphous metal film layer having the supercooled liquid region is attached to the mold base by PVD (Physical Vapor Deposition), strong adhesion can be achieved.

A method for producing a molding die for an optical element according to claim 6 is the invention according to any one of claims 1 to 5 , wherein the amorphous metal film layer having the supercooled liquid region is formed by sputtering. The target element having the same composition as the amorphous metal having the desired supercooled liquid region ejected by the high energy generated in the plasma collides with the mold substrate, and the amorphous metal Since the film layer is formed, the film layer has a high density and can achieve strong adhesion.

The method for producing a molding die for an optical element according to claim 7 is the invention according to any one of claims 1 to 5 , wherein the amorphous metal film layer having the supercooled liquid region is ion-plated. It is characterized by forming by. In the ion plating process, an element having the same composition as that of an amorphous metal having a supercooled liquid region is evaporated in a high vacuum to ionize the evaporated flow. Since this ionized evaporation flow is accelerated toward the mold base to which a negative voltage is applied, the film can be deposited by colliding with the mold base with high energy, and a strong adhesion can be achieved. At this time, since the amorphous metal having the supercooled liquid region can be chemically activated by reacting with the gas, a film having good adhesion can be obtained at a low reaction temperature.

In the method for producing a molding die for optical elements of the present invention, the amorphous metal film layer having the supercooled liquid region may be formed by vapor deposition . Thereby, the thickness of the film layer can be made uniform and strong adhesion can be achieved.

The method for producing a molding die for an optical element according to claim 8 is the invention according to any one of claims 1 to 5 , wherein the amorphous metal film layer having the supercooled liquid region is formed by a CVD process. It is characterized by that. The amorphous film layer having the supercooled liquid region is attached to the mold base by a CVD (Chemical Vapor Deposition) process, so that the same composition as the amorphous metal film layer having the desired supercooled liquid region is obtained. Since the gasified element of the ratio is formed as a film layer by a chemical reaction, the thickness of the film layer is uniform, the throwing power is improved, and strong adhesion can be achieved.

The method of manufacturing a molding die for optical element of the present invention, the surface roughness can also adjust the range of Ra = 1 to 50 [mu] m by sandblasting. Thereby, efficient roughness adjustment is possible. In rough surface processing using sandblasting, it is practically difficult to adjust the roughness below Ra 1 μm, and if the surface of the mold base is roughened to exceed 50 μm, the subsequent amorphous metal When forming a film layer, film defects such as pinholes are likely to occur. Therefore, when sandblasting is used, a surface roughness in the range of Ra = 1 to 50 μm is appropriate.

In the method for producing a molding die for optical elements of the present invention, the surface roughness can be adjusted within a range of Ra = 0.0.10 to 50 μm by an etching step using an acid or alkali solution . As a result, the surface roughness can be controlled by temperature and time, so that the surface roughness can be adjusted stably.

In the method for producing a molding die for optical elements of the present invention, the acid or alkali solution may be acetic acid, formic acid, hydrochloric acid, nitric acid, sulfuric acid, chromium etching solution, potassium hydroxide, sodium hydroxide, hydrocyanic acid, potassium ferricyanide, peroxide. hydrogen water, one of the solutions of aqua regia may be have use of. By using these, the surface roughness can be adjusted efficiently and stably.

In the method for producing a molding die for optical elements of the present invention, the surface roughness can be adjusted within a range of Ra = 0.0.10 to 50 μm by an etching process using a sputtering method. For example, if the mold base is placed in a vacuum, and Ar particles are brought into contact with the mold base by plasma discharge generated in proximity to roughen the surface, the mold before and after etching The possibility of contaminating the etched surface of the substrate with other substances can be reduced.

The method for producing a molding die for an optical element according to claim 9 is the invention according to any one of claims 1 to 8 , wherein the amorphous metal film layer having the supercooled liquid region and the die It is selected from the group of noble metal elements such as Pt, Ir, Pd, Au, Ru, Rh, and Ag and the group of transition metal elements such as Fe, Co, Ni, Cr, W, Ti, Mo, and Zr. A functional film having a thickness of 0.01 μm to 20 μm, which is made of any one of the above elements or a combination of any two or more elements, is formed.

  By forming the functional film between the mold base and the amorphous metal film layer having the supercooled liquid region, the adhesion between the mold base and the film layer can be further increased. Can be increased.

A method for producing a molding die for an optical element according to claim 10 is the invention according to any one of claims 1 to 8 , wherein the amorphous metal film layer having the supercooled liquid region and the die A film layer having any one component selected from the group consisting of alumina, chromina, WC, silicon nitride, carbon nitride, TiN, TiAlN, zirconia, diamond, diamond-like carbon, and carbon between the substrates. A functional film is formed by forming a film thickness of 0.01 μm to 20 μm.

  The functional film made of the above-described material is formed between the mold base and the amorphous metal film layer having the supercooled liquid region, thereby forming the mold base and the film layer. In addition to enhancing the adhesion, it is possible to expect a heat insulation effect by the functional film, an oxidation protection effect of the mold base by the functional film, and a mold shape protection effect by the high hardness functional film.

In the method for producing a molding die for optical elements of the present invention, the functional film may be formed by PVD treatment. When the functional film is attached to the mold base by PVD (Physical Vapor Deposition) treatment, strong adhesion can be achieved.

The method for producing a molding die for an optical element according to claim 11 is characterized in that, in the invention according to claim 9 or 10 , the functional film is formed by a sputtering process, so that high energy generated in plasma. Since the functional film material ejected collides with the mold base material to form a film layer, the density of the film layer is high and strong adhesion can be achieved.

According to a twelfth aspect of the present invention, there is provided a method for producing a molding die for an optical element according to the ninth or tenth aspect , wherein the functional film is formed by an ion plating process. In the ion plating process, the material of the functional film is evaporated in a high vacuum, and the evaporated flow is ionized. Since this ionized evaporation flow is accelerated toward the mold base to which a negative voltage is applied, the film can be deposited by colliding with the mold base with high energy, and a strong adhesion can be achieved. At this time, since the material of the functional film can be chemically activated by reacting with the gas, a film having good crystallinity can be obtained at a low reaction temperature.

In the method for producing a molding die for optical elements of the present invention, the functional film may be formed by vapor deposition . Thereby, the thickness of the film layer can be made uniform and strong adhesion can be achieved.

According to a thirteenth aspect of the present invention, there is provided a method for manufacturing an optical element molding die according to the ninth or tenth aspect of the present invention, wherein the functional film is formed by a CVD process. By attaching the functional film to the mold base by a CVD (Chemical Vapor Deposition) process, the film layer is formed by a chemical reaction of the material of the gasified functional film. Can improve adhesion and achieve strong adhesion.

The method for producing a molding die for optical elements according to claim 14 is the invention according to any one of claims 9 to 13 , wherein the functional film is formed on the surface of the die base material before the functional film is formed. The surface roughness of the surface of the mold base is adjusted within a range of Ra = 0.0.10 to 50 μm. By roughening the surface of the mold base within a range of Ra = 0.0.10 to 50 μm, the adhesion between the mold base and the functional film can be enhanced.

In the method for producing an optical element molding die of the present invention, the surface roughness can be adjusted within a range of Ra = 1 to 50 μm by a sandblasting process. Thereby, efficient roughness adjustment is possible.

In the method for producing a molding die for optical elements of the present invention, the surface roughness can be adjusted within a range of Ra = 0.0.10 to 50 μm by an etching step using an acid or alkali solution . Thereby, since the surface roughness can be controlled by time, the surface roughness can be adjusted stably.

In the method for producing a molding die for optical elements of the present invention, the acid or alkali solution may be acetic acid, formic acid, hydrochloric acid, nitric acid, sulfuric acid, chromium etching solution, potassium hydroxide, sodium hydroxide, hydrocyanic acid, potassium ferricyanide, peroxide. hydrogen water, one of the solutions of aqua regia may be have use of. By using these, the surface roughness can be adjusted efficiently and stably.

In the method for producing a molding die for optical elements of the present invention, the surface roughness can be adjusted within a range of Ra = 0.0.10 to 50 μm by an etching process using a sputtering method. For example, if the mold base is placed in a vacuum and Ar particles are brought into contact with the mold base by a plasma discharge generated in proximity to roughen the surface, the mold before and after etching The possibility of contaminating the etched surface of the mold base material with other substances can be reduced.

The method for producing a molding die for optical elements according to claim 15 is the invention according to any one of claims 1 to 14 , wherein the outer diameter of the molding die for optical elements is the optical element molded thereby. It is characterized by being 1 mm or more larger than the diameter. That is, by increasing the outer diameter of the mold by 1 mm or more than the diameter of the optical element to be produced, and increasing the volume of the mold base, the heat capacity of the entire mold is also increased. Can be further increased. Normally, the outer diameter of the mold is the same as or almost the same as the diameter of the optical element to be produced (diameter 1 mm or less). In the present invention, the outer diameter of the mold is increased, the volume is increased, The heat capacity of the entire mold is increased.

The method for manufacturing a molding die for optical elements according to claim 16 is the invention according to any one of claims 1 to 15 , wherein the optical surface of the optical element molded by the molding die for optical elements is optically Since the annular zone structure is formed around the shaft, the function of the optical element molded by the optical element molding die manufactured by the manufacturing method can be further enhanced.

The method of manufacturing a molding die for optical element of the present invention, the ring-shaped structure may be an optical path difference providing structure. The function of the optical element molded by the optical element molding die manufactured by the manufacturing method can be further enhanced. As the optical path difference providing structure, a so-called NPS (Non-Periodic Surface) structure or the like is known.

In the method for manufacturing a molding die for optical elements of the present invention, the annular zone structure may be a blazed diffractive structure having a sawtooth cross section in the optical axis direction. The function of the optical element molded by the optical element molding die manufactured by the manufacturing method can be further enhanced.

In the method for manufacturing a molding die for optical elements of the present invention, the annular structure may be a diffractive structure having a step-like cross section in the optical axis direction. The function of the optical element molded by the optical element molding die manufactured by the manufacturing method can be further enhanced. A DOE or the like is known as a step-like diffraction structure.

The method for manufacturing a molding die for optical elements according to claim 17 is the invention according to any one of claims 1 to 16 , wherein the mold optical surface of the molding die for optical elements is only an aspherical shape. Therefore, an optical element having a highly accurate aspheric surface can be produced at low cost.

An optical element molding die according to an eighteenth aspect is manufactured using the method for manufacturing an optical element molding die according to any one of the first to seventeenth aspects.

The optical element of the present invention is preferably molded using the optical element molding die according to claim 18 and has high accuracy and low cost.

The optical element of the present invention is preferably a plastic material and the material.

The optical element of the present invention is preferably a glass material as a material.

The optical element of the present invention is preferably a lenses.

In the optical element of the present invention, the optical element forms an annular structure on an optical surface, and the annular structure changes the aberration of the optical element due to a wavelength change of a light source that irradiates light to the optical element. it may have a function to correct. For example, an optical element suitable for an optical pickup device that records and / or reproduces information on an optical disk can be provided.

In the optical element of the present invention, the optical element forms a zonal structure on the optical surface, the ring-shaped structure may be have a function of correcting the aberration change due to the temperature change of the optical element. For example, an optical element suitable for an optical pickup device that records and / or reproduces information on an optical disk can be provided.

The optical element of the present invention may be the optical surface of the front Symbol optical element, preferably the plurality of projections or depressions are transferred shaped, enhance the function of the optical element. Even if the protrusions or depressions must be arranged at intervals of several tens to several hundreds of nanometers, they can be easily formed by transfer molding without requiring machining. Note that the protrusions or depressions include those in which both protrusions and depressions are mixed.

  In recent years, an attempt has been made to add a new optical function to an optical element by applying a fine structure smaller than several times the wavelength of a light source to be used to the optical surface. For example, the normal focusing function due to refraction of a molded lens and the positive dispersion that occurs as a side effect at that time are utilized by utilizing the large negative dispersion due to diffraction obtained by forming a diffraction groove on the surface of the aspheric optical surface. Of these, it has been put to practical use with a pickup objective lens for an optical disk compatible with DVD / CD to add an achromatic function, which is essentially impossible with refraction alone, to a single optical element. This utilizes the diffractive action of a diffraction groove having a size several tens of times the wavelength of light transmitted through the optical element, and the region that handles the diffractive action by a structure sufficiently larger than the wavelength is called a scalar region. It is.

  On the other hand, it has been found that the light reflection suppressing function can be exhibited by forming the conical projections densely on the surface of the optical surface at a minute interval of a fraction of the wavelength of the light transmitted through the optical element. Yes. That is, the refractive index change at the interface with the air when the light wave enters the optical element is not instantaneously changed from 1 to the medium refractive index as in the conventional optical element, but is arranged at a fine interval. By changing the shape of the protrusions gradually, the reflection of light can be suppressed. The optical surface on which such protrusions are formed has a fine structure called a so-called “eyes”, and individual structures can no longer be obtained by arranging structures finer than the wavelength of light with a period shorter than the wavelength. It works as an average refractive index for light waves without being diffracted. Such a region is generally called an equivalent refractive index region. Regarding such an equivalent refractive index region, see, for example, IEICE Transactions C Vol. J83-C No. 3 pp. 173-181, described in March 2000.

  According to the microstructure of the equivalent refractive index region, it is possible to obtain a large antireflection effect while reducing the angle dependency and wavelength dependency of the antireflection effect as compared with the conventional antireflection coating, but according to plastic molding or the like, Since the optical surface and fine structure can be created at the same time, the lens function and the antireflection function can be obtained at the same time, and there is also a great merit in production such that post-processing such as antireflection coating treatment after molding is unnecessary as in the past. It is considered and is attracting attention. Furthermore, if such a fine structure of the equivalent refractive index region is arranged so as to have directionality with respect to the optical surface, it is possible to give the optical surface strong optical anisotropy. Thus, the birefringent optical element produced can be obtained by molding, and a new optical function can be added in combination with a refractive or reflective optical element. The optical anisotropy in this case is called structural birefringence.

  Between the above-described scalar region and equivalent refractive index region, there is a resonance region in which the diffraction efficiency changes rapidly due to a slight difference in incident conditions. For example, when the groove width of the diffraction ring zone is narrowed, a phenomenon (anomaly) occurs in which the diffraction efficiency rapidly decreases and increases by several times the wavelength. By utilizing the characteristics of this region, a waveguide mode resonance grating filter that reflects only a specific wavelength can be realized with a fine structure, and the same effect as a normal interference filter can be realized with less angular dependence.

In the optical element of the present invention, the projections or depressions may form a fine structure of the equivalent refractive index area. In addition, it is preferable that the space | interval of the said protrusion or a hollow is below the wavelength of the light which permeate | transmits the optical surface of the said optical element.

In the optical element of the present invention, the projections or depressions may form a microstructure which generates an antireflection effect. In addition, it is preferable that the space | interval of the said protrusion or a hollow is below the wavelength of the light which permeate | transmits the optical surface of the said optical element.

In the optical element of the present invention, the projections or depressions may form a microstructure which generates form birefringence. In addition, it is preferable that the space | interval of the said protrusion or a hollow is below the wavelength of the light which permeate | transmits the optical surface of the said optical element. In addition, it is preferable that the space | interval of the said protrusion or a hollow is below the wavelength of the light which permeate | transmits the optical surface of the said optical element.

In the optical element of the present invention, the projections or depressions may form a microstructure of the resonance region. In addition, it is preferable that the space | interval of the said protrusion or a hollow is below the wavelength of the light which permeate | transmits the optical surface of the said optical element.

The optical element of the present invention, prior to Symbol protrusions or indentations preferably are present in a portion of the optical surface of the optical element. By forming fine projections or depressions on the optical surface of the optical element so as to have a plurality of shapes and arrangement patterns, and arranging them partially on the optical surface, the optical surface is locally Therefore, the optical function of these fine structures can be exhibited. As a result, a plurality of optical functions can be incorporated into a single light beam by partially or selectively performing the optical function generated by the shape and arrangement pattern of the projections and depressions of the fine structure on the light beam passing through the optical surface. In this case, it is not always necessary that the projections and depressions of the fine structure exist on the entire optical surface of the optical element. That is, conventionally, it is necessary to combine a plurality of optical elements in order to exhibit a predetermined optical function. However, if the optical element of the present invention is used, a predetermined optical function can be achieved independently, and an optical system can be used. It can be further simplified and a significant cost reduction can be realized. Further, the optical element of the present invention can be easily mass-produced.

The optical element of the present invention, a portion of the optical surface before Symbol optical element, characterized in that the projections or depressions is present having at least a plurality of shapes or arrangement patterns.

  The diffractive structure (diffraction ring zone) used in this specification is a diffraction pattern in which a relief formed as a substantially concentric ring zone centered on the optical axis is provided on the optical surface of an optical element (for example, a lens). This means a diffractive surface having a function of condensing or diverging a light beam. For example, when the cross section is viewed on a plane including the optical axis, each annular zone is known to have a sawtooth shape, but such a shape is included. The diffraction zone is also called a diffraction groove.

  When the present invention is applied, the shape and arrangement period of individual microstructures, such as the annular structure and the arrangement of protrusions (or depressions), are not relevant. Whatever the fine structure, if it is made for the purpose of adding a new function to the optical element, the molding die for the optical element or the optical element molded by the optical element can be used in the present invention. Included in the category. Further, the function to be newly added is not limited to the function for reducing aberration. The case where the aberration is intentionally increased according to the characteristics of the optical system is also included in the scope of the present invention as long as it is performed for the purpose of finally bringing it closer to the ideal aberration.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the shaping | molding die for optical elements which can reduce a molding cycle time while having durability, and can shape | mold an optical element with high precision, and the molding die for optical elements manufactured by it A mold and an optical element molded thereby can be provided.

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are diagrams showing a manufacturing process of a molding die for optical elements. First, the cylindrical mold base 10 is manufactured. As a material of the mold base 10, specifically, as a material having a thermal conductivity of 20 W / Km or less, zirconia, alumina, macor, macerite [Al ₂ O ₃ · K ₂ O · B ₂ O ₃ · F] Inconel alloy, Ti alloy, stainless steel alloy (SUS304), and the like. As an example, when a zirconia base material (NPZ-1) is used, first, zirconia powder is sintered into an approximate shape of a mold base (hot press). After that, the blank mold base is ground and the dimensional accuracy of the outer shape is obtained. Except for the optical element molding transfer surface of the mold (hereinafter referred to as the mold optical surface), the outer peripheral portion and the end surface are processed by a cutting process using a diamond tool and a grinding process using the diamond tool. In this case, it is preferable that the processing accuracy of the outer peripheral portion is a shape accuracy of 2 μm or less and the surface roughness is Ra 100 nm or less.

  On the processed mold base 10, a functional film Cr is formed to a thickness of 0.01 to 50 μm on the mold optical surface. Examples of the film forming apparatus include a sputtering apparatus, a vapor deposition apparatus, ion plating, and CVD. When forming a functional film with a sputtering device, the film formation conditions vary depending on the device. For example, in an Ar atmosphere of 0.1 Pa, the distance from the target to the mold optical surface is RF300W. Set to 90 mm. Although it depends on the apparatus, adjustment is performed because the film formation rate changes from about 1 μm / h to 20 μm / h depending on the distance.

  A major function of the functional film is enhancement of adhesion between the mold base and an amorphous metal film layer having a supercooled liquid region formed in a subsequent process. In particular, when an amorphous metal film layer having a supercooled liquid region is formed on a ceramic material such as zirconia, it is preferable to provide a functional film. When an amorphous metal film layer having a supercooled liquid region is formed on a zirconia mold base without a functional film, the adhesion force is about 50 gf according to the measurement of the adhesion force of the film by an adhesive tape peeling test. However, by forming the functional film Cr with a film thickness of 0.01 to 1 μm, the adhesion can be increased to 1,000 gf or more. Therefore, it is possible to prevent peeling of the amorphous metal having the supercooled liquid region due to the close contact between the molding resin and the mold optical surface when used as a molding die.

The adhesive tape peeling test conducted by the present inventors will be described. The adhesive tape peeling test is a method in which an adhesive tape is applied to the surface of a film layer, and then the film layer is peeled off rapidly and strongly, and the maximum tensile load recorded at the time of peeling is measured. This is evaluated as adhesion. The upper limit of the adhesion strength of this measurement is determined by the adhesion strength of the test tape. Double-sided tape used in the evaluation test, in the plane of about 30 mm ^2, since a tape having adhesion 1,000 gf, the upper limit of the adhesive strength can be measured was 1,000 gf. In addition, a clearer determination can be made by carrying out a test after forming a streak reaching a substrate that can form a square of 6 to 7 mm on one side with a sharp blade on the film layer surface before the tape is applied.

  After obtaining a functional film layer having a desired thickness, an amorphous metal film layer having a supercooled liquid region is formed using a film forming apparatus such as sputtering (see FIG. 1). The mold base 10 is attached to a film forming apparatus for metal glass (also referred to as amorphous metal having a supercooled liquid region) shown in FIG. More specifically, in FIG. 1, a target support base 201 that supports the target T is placed in the processing chamber P covered with the casing 200, and the mold surface is made to correspond to the base surface. A sample holder 202 that holds the substrate 10 is disposed. A cooling pipe is formed inside the target support base 201, and cooling water for temperature adjustment can be circulated through the cooling pipe via an external control device 203.

  The processing chamber P is connected to a turbo molecular pump 204 via a valve V1, and the turbo molecular pump 204 is connected to a rotary pump 205 via a valve V2. The inside of the processing chamber P is sucked by the two pumps 204 and 205 to a pressure of about 10-1 to several Pa, and contains Ar molecules.

  The film forming conditions vary depending on the film forming conditions such as the film thickness and the apparatus. For example, in an Ar atmosphere of 0.5 Pa, RF 500 W, from the target to the film to be formed, to the mold optical surface Set the distance to 90 mm. Although it depends on the apparatus, adjustment is performed because the film formation rate changes from about 1 μm / h to 20 μm / h depending on the distance. The closer the sample is, the higher the film formation rate is. However, adjustments are necessary because of problems such as coarse particles in the formed film. Confirmation of the amorphous state of a sample formed by this method can be done by observing the endothermic reaction that occurs when the amorphous state undergoes a phase transition to the supercooled liquid region using a DSC (heat flux differential scanning calorimeter), or This can be confirmed by obtaining a pattern in which no peak due to the crystal structure peculiar to the amorphous state is observed by observation with an X-ray diffractometer. By such a method, it is possible to form a metal glass film on the optical surface of a molding die for optical use relatively easily as compared with the conventional method for producing bulk metallic glass.

  The blank mold that has completed the process of forming the amorphous metal film layer having the supercooled liquid region is cut using a diamond tool for processing the outer peripheral portion and the end face portion except for the mold optical surface, and diamond. It is performed in a grinding process using a tool.

  Diamond cutting is performed using a single crystal diamond tool T shown by the dotted line in FIG. 2 with an ultra-precision lathe (not shown), etc., so that conventional die production by electroless nickel plating is performed. Although the processing steps are basically the same as the method, the mold optical surface MGa and the geometric dimension reference surface transfer surface MGb are rapidly and densely formed by PVD processing or CVD processing and are not subjected to chemical plating processing compared to the conventional method. Therefore, it can be said that the excellent features are that there are no defects such as pinholes and that the process delivery time is fast and that the machinability is very good, so that tool wear is small and shape creation by cutting is easy.

  However, the machining process of the mold optical surface is not limited to diamond cutting. Taking advantage of the ease of transfer of the amorphous metal film layer with the supercooled liquid region, for example, by making a master mold with a fine structure and copying it from the master mold by molding transfer method, according to the ring shape of the optical element etc. It is also possible to form a fine structure on the mold optical surface (see Japanese Patent Application Laid-Open Nos. 2003-154529 and 2003-160343). According to this method, if one master mold is prepared, it is possible to easily produce molds by transferring the surface shape, eliminating the need to create mold optical surfaces one by one by machining. , The mold production period can be greatly shortened.

  In this case, it is preferable that the processing accuracy of the outer peripheral portion is dimensional accuracy of 2 μm or less and the surface roughness is Ra 100 nm or less. When the die base material is a hard and brittle hard-to-work material such as zirconia, a dimensional accuracy is achieved in the grinding process. After the outer peripheral portion processing step is finished, predetermined processing of the mold optical surface MGa is performed. That is, the amorphous metal film layer having the supercooled liquid region of the mold optical surface MGa is cut with a diamond tool to obtain a mold optical surface shape having a fine structure and / or an aspherical shape. The shape accuracy is preferably 50 nm or less, and the surface roughness is preferably Ra 5 nm or less. The predetermined processing is not limited to machining. By the way, in the mold outer periphery processing step, when the mold base is ceramic, the amorphous metal film layer or functional film layer having the supercooled liquid region adhering to the outer periphery is scraped off in the grinding process, and the ceramic substrate In some cases, the material may be exposed to increase the outer dimensional accuracy. By exposing the ceramic base material, the ceramic base material is hard and has a low coefficient of friction even in the structure where the mold slides up and down to take out the molded product during optical element molding. The occurrence of galling between the molds can be suppressed, reliable operation can be performed, and wear of the mold and the mold peripheral member which is a sliding partner can be suppressed. However, in the present invention, it does not matter whether or not the outer peripheral portion is exposed as a base material.

  As described above, an amorphous metal film layer having a supercooled liquid region on the mold optical surface MGa using a mold material having a thermal conductivity of 1 to 20 W / mK for the mold base 10 is formed to a thickness of 10 to 500 μm. An optical element molding die 10 ′ for molding the formed optical element having a diameter of 5 mm or less can be obtained. The outer diameter φ (FIG. 2) of the optical element molding die 10 ′ is preferably 1 mm or more larger than the diameter of the optical element molded thereby.

  FIG. 3 is a cross-sectional view of a die set including an optical element molding die 10 ′ for forming a lens which is an example of an optical element. An optical element molding die 10 ′ in which an amorphous alloy MG is formed as described above and an optical element molding die 11 ′ in which an amorphous alloy MG ′ is formed in the same manner are used as a mold. The optical surfaces MGa and MGa ′ and the geometric dimension reference surface transfer surfaces MGb and MGb ′ are opposed to each other so that they are inserted into the die set dies 13 and 14 and the molten plastic material PL is usually fed from a gate (not shown). Similarly to the injection molding, a lens having a desired shape can be obtained by injecting between the optical element molding dies 10 'and 11' and further cooling.

  FIG. 4 is an enlarged perspective view showing an example of an optical surface of a lens formed by such a molding die for optical elements. 4A shows a configuration in which a large number of fine cylinders C are formed in a matrix on the optical surface of the lens as an example of a plurality of protrusions (an example of a fine structure of an equivalent refractive index region). For example, when such an objective lens is used as a lens of a DVD recording / reproducing optical pickup device, the light transmitted through the lens is in the vicinity of 650 nm. Accordingly, when the interval Δ between the minute cylinders C is set to 160 nm, the light incident on the objective lens is hardly reflected, and an objective lens having an extremely high light transmittance can be provided.

  In FIG. 4B, on the optical surface of the lens, a number of fine triangular pyramids T separated by an interval Δ are formed as an example of a plurality of protrusions, and the same remarkable effect as in FIG. Have. As this space | interval (DELTA), since scattering is reduced as it is 0.1-0.2 micrometer or less, it is preferable. In FIG. 4C, a large number of fins F (example of fine structure of structural birefringence) separated by a distance Δ are formed on the optical surface of the lens as an example of a plurality of protrusions. The length of the fin F is longer than the wavelength of transmitted light (650 nm or more in the above example). A lens having such a configuration has a so-called polarization effect in which light having a vibration surface is transmitted in a direction along the fin F, but light in a direction intersecting the fin F is not transmitted. In FIG. 4D, a blazed diffractive annular zone D having a sawtooth cross section in the optical axis direction is formed on the optical surface of the lens as an example of the annular zone structure centered on the optical axis. Regarding the diffraction zone D, for example, Japanese Patent Laid-Open No. 2001-195769 describes in detail chromatic aberration correction and temperature correction, which are effects according to the shape thereof, and thus the following description is omitted. Other ring zones such as NPS and DOE can be formed. 4A to 4C show an example in which these protrusions are provided on a flat surface for the sake of simplicity, but the bottom surface thereof is a curved surface having an appropriate curvature such as a spherical surface or an aspherical surface. It may be provided on the curved surface.

FIG. 5 is a schematic cross-sectional view of a mold used for a comparative test conducted by the present inventors. The specifications of each mold will be described.
FIG. 5A: Example 1: Ceramic (mold base) + metal glass film layer FIG. 5B: Example 2: Ceramic (mold base) + functional film + metal glass film layer diagram 5 (c): Comparative Example 1: Metal (mold base) + plating film layer FIG. 5 (d): Comparative Example 2 (corresponding to Non-Patent Document 1): Ceramic (mold base) + plating film FIG. 5E: Comparative Example 3 (corresponding to Patent Document 1): Ceramic (mold base) + metal layer + plating film layer

  The present inventors performed comparative evaluation using the above molds. The evaluation results are shown in Table 1.

In Table 1, the transfer performance of the mold is evaluated by how accurately an optical element having a diffractive structure used in an optical pickup device can be transferred. Since the optical element used in the optical pickup device for DVD / CD and the optical element used in the optical pickup device for BD (Blu-ray Disc) / HD DVD are different from each other in the wavelength of laser light, BD / Since the fine structure of the optical element used in the optical pickup device for HD DVD has a finer shape, higher transfer performance is required. Here, the evaluation results have the following meanings.
◎: Very good transferability ○: Good transferability △: Average transferability ×: Bad transferability

In Table 1, the durability of the mold is evaluated based on the number of shots at which the film layer peels during molding. Here, the evaluation results have the following meanings.
◎: More than 10,000 shots can be molded ○: Thousands of shots can be molded △: Several hundred shots can be molded ×: Within tens of shots

In Table 1, the change in the shape of the mold is, for example, 10 shots, 100 shots, 1000 shots, 5000 shots, 10000 shots, and the like. Evaluate with. Here, the evaluation results have the following meanings.
◎: No change in shape ○: Although there is a change in shape, the deformation remains at a level where there is no practical problem. △: A deformation that cannot be ignored occurs, but it can be handled by changing the molding conditions. ×: A deformation that cannot be ignored occurs. However, it cannot be used as a mold for optical elements

In Table 1, the machinability of the mold is evaluated by the surface roughness after cutting using a diamond tool. Here, the evaluation results have the following meanings.
A: Ra is less than 1 nm B: Ra is 1 to 10 nm
Δ: Ra is 10 to 50 nm
X: Ra exceeds 50 nm

In Table 1, the processing period of the mold is evaluated based on the total time required for manufacturing the mold. Here, the evaluation results have the following meanings.
◎: Mold processing period is within a few weeks ○: Mold processing period is about 1 to 2 months △: Mold processing period exceeds 2 months

  Considering the evaluation results, with respect to the transfer performance, Examples 1 and 2 were very good in comparison with Comparative Examples 1 and 2. In addition to the overall shape, it is important for molding and transfer in optical elements such as DVD compatible lenses and BD (Blu-ray) / HD DVD lenses. The transfer performance is most effective for the performance of the optical element. From the comparison results, in the case of Examples 1 and 2, the sagging of the groove (described later with reference to FIG. 6) is reduced to about 1/2 to 1/4. Regarding the transfer of the fine structure in the optical element for the optical pickup device for BD / HD DVD, which tends to have a smaller sheath pitch, it is difficult to put it to practical use in the configuration of Comparative Example 2, whereas Examples 1 and 2 Both were good.

  FIG. 6 is a schematic cross-sectional view showing a filling state of the optical element material with respect to the microstructure of the mold optical surface in a comparative test conducted by the present inventors. FIG. 6A is a comparative example in which an Fe-based material is used as a mold base, and an electroless nickel plating is formed thereon to form a blazed microstructure (pitch 10 μm, height 1 μm). FIG. 6B shows an embodiment in which zirconia is used as a mold base material and an amorphous metal film layer having a supercooled liquid region is formed on the same to form the same blazed microstructure.

  Resin was injected using these molds, the microstructure was cut before mold release, and the electron microscope was used to observe whether the resin had entered and transferred to the deepest part of the blaze groove. When the blazed microstructure created on the optical surface of the mold is molded and transferred to the optical element, the molten resin cannot enter the bottom of the blazed groove of the microstructure, and therefore cannot be transferred completely, as shown in FIG. As shown, when a defective transfer portion occurs in the surface shape of the optical element transferred and molded by the blaze groove on the mold optical surface, this is called sagging. By measuring the length Δ of the sagging pitch direction (FIG. 6A), it can be used as an index for evaluating the transferability of the optical element fine shape. In the comparative example shown in FIG. 6A, the sag was 1 to 2 μm. However, in the example shown in FIG. 6B, the sag is 0.5 μm or less. Was reduced to 1/2 to 1/4, and the effect was confirmed.

  As for durability, Examples 1 and 2 gave very good results compared to Comparative Examples 2 and 3. In particular, in the configuration of Comparative Example 2, peeling occurred before reaching a predetermined number of shots, whereas both Examples 1 and 2 were good. In addition, compared with Example 1, Example 2 has shown durability 20 times or more. On the other hand, as in the comparative example, the combination of the ceramic base material and the plating layer is not compatible and the film layer is easily peeled off. In particular, it has been found that repeated thermal shock makes it easy to peel.

  Regarding the mold shape change, Comparative Examples 2 and 3 and Examples 1 and 2 were all good. If a hard material such as ceramic is used for the mold base, it is effective for suppressing the shape change of the mold.

  As for cutting performance, Examples 1 and 2 gave good results compared to Comparative Examples 1 to 3. Since the amorphous metal film layer having the supercooled liquid region is densely formed by sputtering, the machinability is very good, and particularly excellent in the cutting of the fine structure.

  Regarding the processing period of the mold, Examples 1 and 2 gave good results compared to Comparative Examples 1 to 3. It is necessary to perform ceramic spraying or plating film formation on the mold base because only a simple process of sputtering an amorphous metal film layer having a supercooled liquid region is necessary. Compared to this, the small turning is effective, the die machining time is shortened, and the die manufacturing cost is reduced.

It is a schematic block diagram of the sputtering device used in order to manufacture the shaping die for optical elements. It is a schematic sectional drawing of the shaping die for optical elements. It is sectional drawing of the die set containing the shaping die for optical elements for forming the lens which is an optical element. It is a perspective view which expands and shows the optical surface of the lens formed with the shaping die for optical elements. It is a schematic sectional drawing of the metal mold | die used for the comparative test conducted by the present inventors. It is a schematic sectional drawing which shows the filling state of the optical element material with respect to the fine structure of a metal mold | die optical surface in the comparative test which the present inventors performed.

Explanation of symbols

10 Mold base 10 'Optical element molding die MG Amorphous metal having supercooled liquid region

Claims (18)

  After adjusting the surface roughness of the mold base made of a ceramic material having a thermal conductivity of 1 to 20 W / mK within a range of Ra = 0.0.10 to 50 μm, the surface is coated with Pt, Ir, Supercooling containing at least one element of at least one of Au, Pd, Ru, Rh, Fe, Co, Ni, Zr, Al, Ti, Cu, W, Mo, Cr, B, and P in an amount of 20 to 80 mol% or more A method for producing a molding die for an optical element, wherein a film optical surface is formed by forming an amorphous metal film layer having a liquid region and subjecting the film layer surface to predetermined processing.   The method for producing a molding die for optical elements according to claim 1, wherein the molding die for optical elements is used for molding an optical element having a diameter of 5 mm or less.   The thickness of the film layer of the amorphous metal formed on the surface of the mold base is 10 to 500 µm, The production of the molding die for optical elements according to claim 1 or 2 Method.   The method for producing a molding die for an optical element according to any one of claims 1 to 3, wherein the amorphous metal having the supercooled liquid region has a thermal conductivity of 1 to 20 W / mK. The mold base is made of any one of zirconia, alumina, macor, and macerite [Al ₂ O ₃ · K ₂ O · B ₂ O ₃ · F] ceramics. 5. A method for producing a molding die for optical elements according to any one of 4 above.   6. The method for producing a molding die for an optical element according to claim 1, wherein the amorphous metal film layer having the supercooled liquid region is formed by sputtering.   6. The method for producing a molding die for an optical element according to claim 1, wherein the amorphous metal film layer having the supercooled liquid region is formed by an ion plating process.   6. The method for producing a molding die for an optical element according to claim 1, wherein the amorphous metal film layer having the supercooled liquid region is formed by a CVD process.   Pt, Ir, Pd, Au, Ru, Rh, Ag noble metal element group and Fe, Co, Ni, between the amorphous metal film layer having the supercooled liquid region and the mold base. A functional film having a thickness of 0.01 μm to 20 μm made of any element selected from the group of transition metal elements of Cr, W, Ti, Mo, and Zr, or a combination of any two or more elements The method for producing a molding die for optical elements according to claim 1, wherein:   Between the amorphous metal film layer having the supercooled liquid region and the mold base, alumina, chromina, WC, silicon nitride, carbon nitride, TiN, TiAlN, zirconia, diamond, diamond-like carbon 9. The functional film is formed by forming a film layer having any one kind of component selected from the group of carbons to a film thickness of 0.01 μm to 20 μm. The manufacturing method of the shaping die for optical elements of description.   The method for producing a molding die for optical elements according to claim 9 or 10, wherein the functional film is formed by a sputtering process.   The method for producing a molding die for an optical element according to claim 9 or 10, wherein the functional film is formed by an ion plating process.   The method for producing a molding die for optical elements according to claim 9 or 10, wherein the functional film is formed by a CVD process.   The surface roughness of the surface of the mold base is adjusted within a range of Ra = 0.010 to 50 μm before forming the functional film on the surface of the mold base. The manufacturing method of the shaping die for optical elements in any one of 9 thru | or 13.   15. The optical element molding die according to claim 1, wherein an outer diameter of the optical element molding die is 1 mm or more larger than a diameter of the optical element molded thereby. Method.   The optical element according to any one of claims 1 to 15, wherein a ring zone structure centering on the optical axis is formed on an optical surface of the optical element molded by the molding die for the optical element. Manufacturing method of a mold.   The method for producing an optical element molding die according to any one of claims 1 to 16, wherein a mold optical surface of the optical element molding die has only an aspherical shape.   An optical element molding die manufactured using the method for manufacturing an optical element molding die according to any one of claims 1 to 17.

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