JPH07105560A - Optical device and its production - Google Patents

Abstract

PURPOSE:To obtain an optical device such as an optical pickup and to obtain its production method by which bad influences of thermal expansion of a resin material on optical system can be decreased as much as possible, a light-weight low-cost device can be produced, and further, workability can be improved. CONSTITUTION:Optical parts are adjusted and arranged in a die 19 coated with a mold release agent such as fluorine-silicone coating agent and are temporarily fixed with an adhesive or mechanical fixing parts such as screws. Then, a light-transmitting resin 20 is charged from a dispenser or injection molding machine into the space among the optical parts. After the light-transmitting resin 20 is hardened, the group of optical parts bonded with the light- transmitting resin 20 is released from the die. Then a moisture-resistant coating material is applied on the surface of the light-transmitting resin 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup or the like which is provided with a plurality of optical components and is required to have a high positioning accuracy among the optical components such that the influence of thermal expansion of the light-transmitting resin material cannot be ignored. The present invention relates to an optical device and a manufacturing method thereof.

[0002]

2. Description of the Related Art An optical pickup for a magneto-optical disk is an example of an optical device which requires highly accurate positioning between a plurality of optical components. 7 and 8 show the structure of an optical pickup of the type currently mass-produced. This optical pickup is configured by arranging a condensing optical system, a servo optical system, and a reproducing optical system on a metal substrate 18 made of, for example, aluminum die cast. Each optical system will be described below.

The focusing optical system comprises a semiconductor laser element 1, a collimating lens 2, a shaping prism 3, a beam splitter 4, a total reflection prism 5, an objective lens 6, a lens driving device 7 and an electromagnet 8. The semiconductor laser element 1 serving as a light source is arranged on the rear side of the right end of the metal substrate 18 which is long in the left and right, and the laser beam emitted from the semiconductor laser element 1 toward the left side is collimated by the collimator lens 2. To be done. The collimated laser beam is shaped by the shaping prism 3, and then guided to the objective lens 6 via the beam splitter 4 and the total reflection prism 5. The laser beam that has passed through the objective lens 6 is focused and irradiated onto the information recording surface of the magneto-optical disk D arranged thereon. The lens driving device 7 moves the objective lens in the focus direction and the tracking direction.

Explaining a little now, the focusing optical system focuses the laser beam emitted from the semiconductor laser device 1 on the information recording surface of the magneto-optical disk D as spot light having a diameter of about 1.6 μm. The electromagnet 8 generates an auxiliary magnetic field for recording / erasing, and the magneto-optical disc D is generated according to the light intensity of the focused spot.
Record magnetic information on.

The servo optical system comprises a condenser lens 9, a cylindrical lens 10 and a light receiving element 11 having a four-division structure. The light receiving element 11 is formed of, for example, a photodiode. Return light reflected from the magneto-optical disk D is guided to the light receiving element 11, and the light receiving element 11 photoelectrically converts the return light to detect a servo signal. More specifically, the focus servo signal is detected from the return light from the magneto-optical disk D by the astigmatism detection method, and the tracking error signal is detected by the push-pull detection method. Then, the servo signal thus detected is transferred to the lens driving device 7
Or to a pickup coarse movement device (not shown).

The reproducing optical system includes a beam splitter 12,
It is composed of a half-wave plate 13, a condenser lens 14, a polarization beam splitter 15, and a photodiode 16. The reproduction optical system uses the polarization beam splitter 15 as an analyzer, detects a magnetic signal on the magneto-optical disk D as rotation of the deflection angle of reflected light, and reproduces information.

Reference numeral 17 in the drawing denotes an adjusting mechanism for the optical components arranged in each optical system. The adjusting mechanism 17 is used to adjust the positioning between the optical components. There is.

By the way, in such an optical pickup, there are many constituent parts, and since the adjusting mechanism 17 is incorporated, there is a limit in reducing the size and weight of the optical pickup. Moreover, the adjusting mechanisms 17, 17 ...
Since it takes a lot of time to perform the adjustment work using, there is a limit in achieving mass productivity and cost reduction.

In order to solve such a problem, an optical pickup device having a hermetically sealed structure disclosed in Japanese Patent Laid-Open No. 3-228234 has been proposed (hereinafter referred to as a first conventional example). As shown in FIGS. 9 and 10, the optical pickup device of the first conventional example has a semiconductor laser 3
1. Micro optics that forms an optical path by aligning the optical axes of the optical components of the metal substrate 35 on which optical components such as the collimator lens 32 are mounted, and filling the optical components with the light-transmitting synthetic resin 33 to form an optical circuit. The system, the substrate 35, and the periphery of the micro optical system are covered with a light absorbing synthetic resin 36 to form an integrated structure.

Explaining a little now, in this optical pickup, an adjusting mechanism is provided on the side of the external production equipment, and the thickness of the substrate 35 is reduced by that much, the lack of strength is compensated, and external light and stray light are blocked. The optical path of the component is filled with the light transmitting synthetic resin 33.

Further, in Japanese Patent Laid-Open No. 62-117150, there is shown in FIG.
As shown in FIG. 1 and FIG. 12, an optical pickup is proposed in which the inside of a flat transparent substrate 40 is used as an optical path, and optical components such as a light emitting element 41 are attached to the surface of the substrate 40 to reduce the size and weight. (Hereinafter referred to as the second conventional example).

Further, even the currently mass-produced facsimile machines have the same problems as the above-mentioned optical pickup, and as a facsimile machine which solves these problems,
There is one disclosed in JP-A-2-301715 (hereinafter referred to as a third conventional example).

In the third conventional example, as shown in FIG. 13, a transparent lens is formed on the surface of the transparent substrate 50 by the photolithography advanced in the semiconductor manufacturing process for the purpose of reducing the number of adjustment points and improving the manufacturability. It is configured to manufacture optical elements such as 51.

[0014]

Generally, in an optical device such as the optical pickup shown in FIGS. 7 and 8, which requires highly accurate positioning between the optical components, A metal material having a smaller linear expansion coefficient is used because the thermal expansion of the substrate that holds and positions the optical component cannot be ignored. Therefore, the weight of the substrate becomes heavy, and there is a limit in reducing the weight. The heavy weight of the substrate becomes a bottleneck in improving the access speed, especially when applied to an optical pickup. In addition, there are limits to achieving low prices. For this reason, lightweight aluminum is generally used as the metal material.

However, the coefficient of thermal expansion of aluminum is so large that it cannot be ignored as compared with the coefficient of thermal expansion of the light-transmitting synthetic resin 33. Therefore, when aluminum is used as the metal substrate of the first conventional example, the coefficient of thermal expansion of both is large. The thermal stress caused by the difference causes deformation such as warpage, which deteriorates the positioning accuracy between the optical components. 2. On the other hand, when a resin material is used, it can be made lighter and cheaper than a metal material. Therefore, recently, in various fields, there is a tendency to use a fiber reinforced resin instead of the metal material. The fiber reinforced resin is generally a resin having a coefficient of linear expansion larger than that of metal and glass or carbon fiber mixed therein, and has a lower coefficient of linear expansion than a metal material. However, since the price is higher than that of commonly used resins, application to the substrate of an optical pickup is a bottleneck in reducing the cost of the optical pickup. 3. In addition, recently, as resin materials have been improved, for example, polyimide resins can obtain a linear expansion coefficient similar to that of glass, but polyimide resins are more expensive than ordinary resin materials at prices of 500 to 1000.
Since it is twice as expensive, there is a cost limitation when it is used as a substrate of an optical pickup. For these reasons, in optical pickups in which the positioning accuracy of each optical component is required to be highly accurate, development of a product that uses a resin substrate and that can eliminate the adverse effects of the thermal expansion of the resin is urgently required. Is the current situation.

On the other hand, in the second conventional example and the third conventional example, a non-resin material such as a glass material is mainly used as the transparent material, and the above-mentioned request cannot be answered.
However, although it is specified in the specification that a resin material can be used, the coefficient of thermal expansion of the resin material is 10 to 30 times larger than that of the glass material. The examples and the third conventional example have not been touched at all, and it is doubtful that the positioning accuracy between the optical components can be maintained with high accuracy when they are used as they are in the above configuration.

Further, in the second conventional example and the third conventional example, since it is assumed that the substrate is a transparent substrate, an opaque fiber reinforced resin cannot be used. Further, when the polyimide resin is used, the cost of the product is similarly increased.

Tables 1 and 2 below show the densities and linear expansion coefficients of typical materials.

[0019]

[Table 1]

[0020]

[Table 2]

The present invention has been made in view of the above circumstances, and it is possible to reduce the adverse effect of thermal expansion of a resin material on an optical system as much as possible, and to reduce the weight and cost of the device. Furthermore, it is an object of the present invention to provide an optical device such as an optical pickup and a method for manufacturing the same that can improve workability.

[0022]

In the optical device of the present invention, an optical path of an optical system formed by a plurality of optical components is arranged in a light-transmissive resin material, and each optical element is made of the light-transmissive resin material. Holds the part, which achieves the above objectives.

Preferably, as the light-transmitting resin material, a material that can offset the temperature change rate of its refractive index and the linear thermal expansion coefficient is used.

Preferably, a moisture resistant coating is applied to the surface of the light transmissive resin material.

The optical device manufacturing method of the present invention comprises a step of positioning and arranging a plurality of optical components on a substrate or a mold coated with a release agent, and light transmission by casting, injection molding or the like. Of a conductive resin material between the plurality of optical components,
After curing the light-transmissive resin material, a step of releasing the plurality of optical components from the substrate or the mold is included, whereby the above object is achieved.

Preferably, the step of applying a moisture resistant coating to the surface of the light transmissive resin material after curing is included.

Further, the method of manufacturing an optical device of the present invention comprises a step of forming a substrate with a light-transmissive resin material by casting, injection molding or the like, and positioning a plurality of optical components on the surface of the substrate with respect to each other. The step of attaching is included, whereby the above object is achieved.

Further, the method for manufacturing an optical device of the present invention comprises the steps of forming a substrate with a light-transmissive resin material by casting, injection molding and the like, and forming a plurality of optical components on the surface of the substrate. The above object is achieved thereby.

Preferably, the step of applying a moisture resistant coating to the surface of the substrate is included.

[0030]

As described above, when the optical path of the optical system formed by a plurality of optical parts is arranged in the light transmissive resin material and each optical part is held by the light transmissive resin material, the light transmissivity is increased. Since it is possible to cancel the thermal expansion of the resin material and the temperature change of the refractive index,
As a result, it is possible to reduce adverse effects of thermal expansion of the light-transmitting resin material on the optical system, that is, misalignment as much as possible.

The reason will be described below with reference to FIGS. 5 and 6. However, in FIGS. 5 and 6, for simplification of description, it is assumed that the two optical components A ₁ and A ₂ are positioned and fixed on the substrate 20 made of a light transmissive resin material. Both optical components A ₁ when the temperature of the substrate 20 is T,
The separation dimension (distance) L of A ₂ is represented by the following formula (1), where T ₀ is the reference temperature of the substrate 20, α is the coefficient of linear thermal expansion, and L ₀ is the separation dimension at that time.

L = L ₀ {1 + α (T−T ₀ )} (1) As shown in Tables 1 and 2 above, the coefficient of linear thermal expansion generally takes a positive value. That is, the dimensions of the material generally increase as the temperature increases.

On the other hand, the present inventors investigated the physical properties of the resin material and found that the temperature change of the refractive index of the resin material had a negative value. That is, the linear thermal expansion coefficient of the resin material and the temperature change of the refractive index have an inverse relationship. Therefore, the present inventors have come to think that the adverse effect of thermal expansion can be reduced as much as possible, if the linear thermal expansion coefficient of the resin material and the temperature change of the refractive index are added, the two cancel each other out. .

FIG. 6 shows a configuration that realizes this idea. That is, the optical path between the optical components A ₁ and A ₂ is filled with a light transmissive resin material, and the substrate 20 made of the light transmissive resin material holds the optical components A ₁ and A ₂ . . In this case, the distance L between the optical components A ₁ and A ₂ is not a geometric distance, but an optical path length that is a product of the geometric distance and the refractive index of the resin material needs to be considered. Here, if the resin temperature is T, the refractive index N _d of the d-line of the light transmitting resin material, the refractive index of the d-line at a temperature T ₀ of the light-permeable resin material N _d0, refractive When the rate of temperature change of the rate is β, it is expressed by the following equation (2).

N _d = N _d0 + β (T−T ₀ ) ... (2) Further, the geometrical distance L of the light transmissive resin material at the temperature T
Is the geometrical distance L ₀ at temperature T ₀ and the coefficient of linear thermal expansion is α
Then, it is expressed in the same manner as the above formula (1).

Therefore, the optical path length L'at the temperature T of the light transmissive resin material is expressed by the following equation (3) as a product of the above equations (1) and (2).

[0037]

[Equation 1]

Here, in the above equation (3), the third term is a quadratic minute quantity and can be omitted. Therefore,
L'is represented by the following formula (4).

[0039]

[Equation 2]

Here, paying attention to the temperature change and comparing the above equations (1) and (4), the linear thermal expansion coefficient α in the equation (1) is N _d0 · α + β in the equation (4). You can see that. Therefore, hereinafter, this N _d0 · α + β will be referred to as a reduced linear thermal expansion coefficient.

On the other hand, Lore which relates the refractive index to the molecular structure
If the ntz-Lorenz equation is modified, the temperature change rate β of the refractive index is expressed by the following equation (5).

[0042]

[Equation 3]

Here, γ is the polarizability and v is the specific volume.

Here, the first term in the equation (5) shows the rate of change of the refractive index due to the temperature change of the polarizability, and the second term shows the rate of change of the refractive index due to volume expansion. As shown in FIG. 3, the first term is smaller than the second term by two orders.

[0045]

[Table 3]

Here, the volume expansion coefficient of the second term in the equation (5) has a relationship of the following equation (6) with the linear thermal expansion coefficient α, assuming that the material is an isotropic material.

[0047]

[Equation 4]

Therefore, the converted linear thermal expansion coefficient N _d0 · α + β
Is expressed by the following equation (7) from the above equations (5) and (6).

[0049]

[Equation 5]

Therefore, if the formula (7) can be made zero, that is, if a new resin having a reduced linear thermal expansion coefficient N _d0 · α + β = 0 is synthesized, the adverse effect of thermal expansion can be theoretically made zero. it can. Although the above description has been given by taking the d-line wavelength as an example, this theory basically holds at any wavelength. Therefore, even if a new resin material is not synthesized, there is a possibility that there is a wavelength at which the expression (7) can be made zero depending on the existing resin material. Therefore, when used at that wavelength, the adverse effect of thermal expansion can theoretically be made zero.

Also in this equation (7), as shown in Table 3, the first term is smaller than the second term, so if neglected, at N _d0 = 2 ^1/2 , the reduced linear thermal expansion coefficient is obtained. Becomes zero. Actually, when the second term is in the order of the first term, the first term cannot be ignored, so that the converted linear thermal expansion coefficient does not become zero at N _d0 = 2 ^1/2 , but N _d0 = 2. ^It can be seen that the light-transmissive resin material in the vicinity of ^1/2 can obtain a linear thermal expansion coefficient on the order of that of the first term, that is, on the order of glass, as can be seen from Table 3.

Table 4 below shows existing light-transmitting resin materials and their converted linear thermal expansion coefficients obtained by the above formula (7).

[0053]

[Table 4]

As can be seen from Table 4, any of the light transmissive resin materials can obtain a reduced linear thermal expansion coefficient of aluminum or less.

In Table 4, the temperature change rate β of the refractive index is actually measured, and the converted linear thermal expansion coefficient using it is also shown, but it was obtained from the second term of the equation (7). The value is different from the one. This is considered to be an error caused by the difference between the measurement temperature of the equation (6) assuming an isotropic material and the linear thermal expansion coefficient and the temperature change rate β of the refractive index. Does not impair the usefulness, that is, the reduction of the adverse effect of thermal expansion.

Since the refractive index of a resin material changes due to moisture absorption, it is preferable to carry out a moisture resistant coating on the surface of the light transmissive resin material in order to prevent this.

As described above, according to the present invention, the optical path of the optical system formed by a plurality of optical components is arranged in the light transmissive resin material, and each optical component is held by the light transmissive resin material. Since the configuration is such that the thermal expansion of the light-transmissive resin material and the temperature change of the refractive index are canceled out, the variation of the optical path length between the optical components due to the thermal expansion can be reduced as much as possible.

[0058]

Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show an optical pickup to which the present invention is applied. The configuration will be described below together with the operation. This optical pickup has a condensing optical system, a servo optical system, and a reproducing optical system, and an optical path between optical parts of each optical system described below is a light-transmissive resin material (hereinafter referred to as a light-transmissive resin) 20. It is arranged inside and each optical component is held only by the light transmissive resin 20. Each optical system will be described below.

The condensing optical system is composed of a semiconductor laser element 1, a collimating lens 2, a shaping prism 3, a beam splitter 4, a total reflection prism 5, an objective lens 6, a lens driving device 7 and an electromagnet 8. The semiconductor laser element 1 serving as a light source is disposed on the rear side of the right end of a substrate made of a light-transmissive resin 20 that is long in the left and right, and the laser beam emitted from the semiconductor laser element 1 toward the left side is a collimating lens. 2 collimates the light. The collimated laser beam is shaped by the shaping prism 3,
It is guided to the objective lens 6 through the beam splitter 4 and the total reflection prism 5. The laser beam that has passed through the objective lens 6 is focused and irradiated onto the information recording surface of the magneto-optical disk D arranged thereon. The lens driving device 7 moves the objective lens in the focus direction and the tracking direction.

Explaining a little now, the focusing optical system focuses the laser beam emitted from the semiconductor laser element 1 on the information recording surface of the magneto-optical disk D as spot light having a diameter of about 1.6 μm. The electromagnet 8 generates an auxiliary magnetic field for recording / erasing, and the magneto-optical disc D is generated according to the light intensity of the focused spot.
Record magnetic information on.

The servo optical system comprises a condenser lens 9, a cylindrical lens 10 and a light receiving element 11 having a four-division structure. The light receiving element 11 is formed of, for example, a photodiode. Return light reflected from the magneto-optical disk D is guided to the light receiving element 11, and the light receiving element 11 photoelectrically converts the return light to detect a servo signal. More specifically, the focus servo signal is detected from the return light from the magneto-optical disk D by the astigmatism detection method, and the tracking error signal is detected by the push-pull detection method. Then, the servo signal thus detected is transferred to the lens driving device 7
Or to a pickup coarse movement device (not shown).

The reproducing optical system includes a beam splitter 12,
It is composed of a half-wave plate 13, a condenser lens 14, a polarization beam splitter 15, and a photodiode 16. The reproduction optical system uses the polarization beam splitter 15 as an analyzer, detects a magnetic signal on the magneto-optical disk D as rotation of the deflection angle of reflected light, and reproduces information.

In addition, the surface of the light transmissive resin 20 is coated with a moisture resistant coating 21.

According to the optical pickup having such a structure, as described in the above-mentioned section of operation, the light transmitting resin 2 is used.
Since the thermal expansion of 0 and the temperature change of the refractive index can be canceled out, the fluctuation of the optical path length between the optical components due to the thermal expansion can be reduced as much as possible. That is, the adverse effect of thermal expansion can be eliminated as much as possible. Therefore, the yield and manufacturing efficiency of the optical pickup can be improved and the price thereof can be reduced. Moreover, since the substrate is made of a resin material, the weight can be reduced and the access speed can be improved.

In addition, since the surface of the light transmissive resin 20 is provided with the moisture resistant coating 21, the refractive index does not change due to moisture absorption. Therefore, the reliability can be further improved.

Next, a method of manufacturing the optical pickup of the present invention will be described with reference to FIGS. As shown in FIG. 3, first, a mold (or substrate) 19 coated with a release agent such as a fluorosilicone coating agent (KP-801M manufactured by Shin-Etsu Chemical Co., Ltd.) is attached to each of the above optical parts (objective lens 6). (Excluding) is adjusted and arranged, and temporarily fixed using a mechanical fastening part such as an adhesive or a screw.

Subsequently, a light-transmissive resin 20 is filled between the respective optical parts with a dispenser or an injection molding machine (FIG. 4).
reference). The method using a dispenser is a casting method, and the method using an injection molding machine is an insert molding method.

When the light-transmissive resin 20 is cured, the mold 19
Then, the optical component group coupled by the light transmissive resin 20 is released. Then, a moisture resistant coating 21 is applied to the surface of the light transmissive resin 20. As the moisture resistant coating material, for example, Teflon AF manufactured by DuPont is used. Moisture resistant coating 2
Since the layer thickness of 1 is extremely thin, it does not adversely affect the size, weight, cost, etc. of the optical pickup.

Next, the objective lens 6 is attached to a predetermined portion of the optical component group, the surface of which is coated with the moisture resistant coating 21 and which is joined by the light transmitting resin 20. At this time, the lens driving device 7 and the electromagnet 8 are attached. Thereby, the optical pickup of the present invention is obtained.

In the above manufacturing method, the optical system is incorporated and then the light-transmitting resin 20 is filled, and the optical components are bonded and held by the light-transmitting resin 20.
The optical pickup of the present invention can also be obtained by a method of molding the light-transmissive resin 20 by casting or injection molding and then positioning and attaching the optical components appropriately.

When molding the light transmissive resin 20,
The optical pickup of the present invention can also be obtained by the method of forming the optical element on the surface thereof.

In the above embodiments, the case where the present invention is applied to the optical pickup has been described, but the present invention can be similarly applied to other optical devices that require highly accurate positioning. Examples of such an optical device include a facsimile device, various sensors such as an optical rangefinder, a copying machine, and a laser printer.

[0074]

According to the optical device of the present invention described above, the optical path of the optical system formed by a plurality of optical components is arranged in the light transmitting resin material, and each optical component is held by the light transmitting resin material. ,
Since the configuration is such that the thermal expansion of the light-transmissive resin material and the temperature change of the refractive index are offset, it is possible to reduce the adverse effect on the optical system due to the thermal expansion of the light-transmissive resin material. Therefore, the yield and manufacturing efficiency of the optical device can be improved, and the cost can be reduced.

Further, as the substrate for holding the optical parts, the usual resin material can be used in place of the metal material and the glass material, so that an excellent optical device which can be reduced in weight and cost and improved in workability is realized. it can.

Further, in particular, according to the optical device of the third aspect, it is possible to realize the optical device which can further improve the reliability.

According to the optical device manufacturing method of the fourth to eighth aspects, it is possible to surely obtain the optical device having the above advantages.

[Brief description of drawings]

FIG. 1 is a plan sectional view showing an optical pickup of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a plan sectional view for explaining a method of manufacturing the optical pickup of the present invention.

FIG. 4 is a sectional view taken along line BB of FIG.

FIG. 5 is a schematic side view showing the principle of the present invention.

FIG. 6 is a schematic side view showing the principle of the present invention.

FIG. 7 is a plan sectional view showing a conventional example of an optical pickup.

8 is a cross-sectional view taken along the line CC of FIG.

FIG. 9 is a plan view showing another conventional example of an optical pickup.

FIG. 10 is a side view of the optical pickup of FIG.

FIG. 11 is a side view showing another conventional example of the optical pickup.

FIG. 12 is a perspective view of the optical pickup of FIG.

FIG. 13 is a side view showing a conventional example of a facsimile device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Semiconductor laser element 2 Collimating lens 3 Shaping prism 4 Beam splitter 5 Total reflection prism 6 Objective lens 7 Lens driving device 8 Electromagnet 9 Condensing lens 10 Cylindrical lens 11 Light receiving element 12 with four-division structure 12 Beam splitter 13 1/2 wavelength plate 14 Condensing lens 15 Polarization beam splitter 16 Photodiode 19 Mold 20 Light-transmissive resin (substrate made of light-transmissive resin) 21 Moisture-resistant coating D Magneto-optical disk

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masahiro Kawamura 22-22 Nagaike-cho, Abeno-ku, Osaka City, Osaka Prefecture

Claims (9)

[Claims] 1. An optical device in which an optical path of an optical system formed by a plurality of optical components is arranged in a light-transmissive resin material, and each optical component is held by the light-transmissive resin material. 2. The optical device according to claim 1, wherein the light-transmissive resin material is capable of canceling out the coefficient of linear thermal expansion and the rate of temperature change of its refractive index. 3. The optical device according to claim 2, wherein a moisture resistant coating is applied to a surface of the light transmissive resin material. 4. The optical device according to claim 1, wherein the optical device is an optical pickup. 5. A step of positioning and arranging a plurality of optical components on a substrate or a mold coated with a release agent, and applying a light-transmissive resin material between the plurality of optical components by casting, injection molding or the like. And a step of releasing the plurality of optical components from the substrate or the mold after curing the light-transmissive resin material. 6. The method of manufacturing an optical device according to claim 5, further comprising a step of applying a moisture resistant coating to the surface of the light transmissive resin material after curing. 7. A method of manufacturing an optical device including a step of forming a substrate from a light-transmissive resin material by casting, injection molding or the like, and a step of mutually positioning and mounting a plurality of optical components on the surface of the substrate. Method. 8. A method of manufacturing an optical component, which includes a step of forming a substrate with a light-transmissive resin material by casting, injection molding, or the like, and a step of forming a plurality of optical components on the surface of the substrate. 9. The method of manufacturing an optical component according to claim 7, further comprising a step of applying a moisture resistant coating to the surface of the substrate.