Cleaning system and cleaning method for optical members

Abstract

This invention provides a cleaning system for optical components and a cleaning system for cleaning optical components made of soft glass material. The cleaning system is characterized by comprising: a cleaning unit for immersing the optical component in a cleaning solution for ultrasonic cleaning; a tap water rinsing unit for rinsing the optical component with tap water; a pure water rinsing unit for rinsing the optical component with pure water; and a drying unit for drying the optical component after the cleaning solution has been removed. The pure water rinsing unit comprises: a hydrogen supply unit for supplying hydrogen gas; a hydrogen-water generation unit for injecting the hydrogen gas into the pure water to generate hydrogen-water; a purified water tank filled with the hydrogen-water; and a control unit for controlling the oxidation-reduction potential of the hydrogen-water. While immersing the optical component in the purified water tank for rinsing, the control unit maintains the oxidation-reduction potential of the hydrogen-water at a predetermined value.

Description

Technical Field

[0001] This invention relates to a cleaning system and method for cleaning optical refractive components such as lenses and prisms used in ophthalmic devices after machining, and particularly to a cleaning system and method for optical components using soft glass materials with low water resistance and detergent resistance. Background Technology

[0002] Generally, in the manufacturing of lenses, prisms, and other optical components, fine glass powder, polishing fluid, dust, and operator fingerprints generated during the cutting process can adhere to the end faces of the optical components. Therefore, a cleaning process is needed to remove these substances. In the past, ultrasonic cleaning equipment was mostly used for cleaning in this process, followed by drying processes such as steam drying, centrifugal drying, and pure water desiccation drying, before the surface is coated and commercialized.

[0003] In particular, the surfaces of optical components made of soft glass are very easy to damage, making it difficult to automate the cleaning process mechanically. The entire process requires manual operation by the operator, or even if part of the process is automated, manual wiping is still required in the final treatment, which raises efficiency issues.

[0004] In this context, Patent Document 1 discloses a cleaning method for optical components that automates a series of processes. The cleaning method in Patent Document 1 includes an ultrasonic water jet cleaning process (first process) to remove physically removable stains, a pure water-based cleaning agent immersion process (second process) to remove water-soluble stains remaining on the surface, a cleaning agent cleaning process (third process) to remove residual grease stains, a pure water rinsing process (fourth process) to remove the cleaning agent, an IPA dehydration process to remove pure water (fifth process), a hydrocarbon solvent cleaning process to remove IPA (sixth process), and a drying process to remove the solvent (seventh process).

[0005] However, in the above-mentioned technology, although there is no problem in cleaning general glass components where the effect of the detergent is small, in the case of optical components made of soft glass materials with poor detergent resistance, if they are immersed in alkaline detergents or pure water during cleaning, there is a problem of so-called blind scratch, which causes the alkali metal components contained in the optical components to dissolve and deteriorate the optical components.

[0006] In addition, Patent Document 2 discloses the following technology: ozone water and hydrogen water are prepared by generating ozone and hydrogen through the electrolysis of water; ozone water and hydrogen water with a specified oxidation-reduction potential (ORP) with adjusted pH are prepared by mixing one of them with one of an acidic solution and an alkaline solution, and then used to clean optical components.

[0007] However, the above-mentioned technology is aimed at cleaning semiconductor substrates. In the example of acidic solution, the pH is 1 to 2, and in the example of alkaline solution, the pH is above 10. The ORP is positive (oxidizing) and the cleaning power is strong, which cannot be applied to the soft glass material of the present invention.

[0008] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2002-273358 Patent Document 2: Japanese Patent No. 3590470 Summary of the Invention The problem the invention aims to solve Currently, in the final stage of the cleaning process for this type of soft glass material, wiping can be performed without the use of alkaline detergents or pure water, but this is time-consuming and therefore inefficient. Furthermore, because optical components made of soft glass are delicate and easily damaged, they are difficult to handle without skilled operation.

[0009] The present invention was made in view of the above circumstances, and its purpose is to provide a cleaning system and method for optical components. The cleaning system and method for optical components are applicable to soft glass materials that are prone to latent damage, and are not dependent on the operator's skill level. The series of processes are made fast and simple through automation, and the cleaning quality after drying is high, with particles difficult to adhere.

[0010] means for solving problems The invention described in technical solution 1 is a cleaning system for cleaning optical components made of soft glass material. It is characterized by comprising: a cleaning unit for immersing the optical component in a cleaning solution for ultrasonic cleaning; a tap water rinsing unit for rinsing the optical component with tap water; a pure water rinsing unit for rinsing the optical component with pure water; and a drying unit for drying the optical component after the cleaning solution has been removed. The pure water rinsing unit comprises: a hydrogen supply unit for supplying hydrogen gas; a hydrogen-water generation unit for injecting the hydrogen gas into the pure water to generate hydrogen-water; a purified water tank filled with the hydrogen-water; and a control unit for controlling the oxidation-reduction potential of the hydrogen-water. While immersing the optical component in the purified water tank for rinsing, the control unit maintains the oxidation-reduction potential of the hydrogen-water at a predetermined value.

[0011] The invention described in technical solution 2 is characterized in that, in the invention described in technical solution 1, the hydrogen gas fed into the hydrogen-water generation unit is 2.6 to 4.0 L per minute / 30 L of pure water.

[0012] The invention described in technical solution 3 is characterized in that, in the invention described in technical solution 1, the pure water rinsing unit has a pH adjustment unit for replenishing an alkaline aqueous solution in order to adjust the pH of the hydrogen water.

[0013] The invention described in technical solution 4 is characterized in that, in the invention described in technical solution 1, it has: a hydrogen water circulation unit that returns hydrogen water used in the water purification tank to the hydrogen water generation unit at a predetermined time; and a filtration unit disposed in the middle of the hydrogen water circulation unit.

[0014] The invention described in technical solution 5 is characterized in that, in the invention described in technical solution 1, the hydrogen supply unit is a water electrolysis device.

[0015] The invention described in technical solution 6 is characterized in that, in the invention described in technical solution 1, the redox potential of the hydrogen water is -400 to 0 mV.

[0016] The invention described in technical solution 7 is characterized in that, in the invention described in technical solution 3, the pH of the hydrogen water is 6.5 to 9.0.

[0017] The invention described in technical solution 8 is a cleaning method for optical components made of soft glass material, characterized by comprising: a cleaning step, in which the optical component is immersed in a cleaning solution for ultrasonic cleaning; a tap water rinsing step, in which the optical component is rinsed with tap water; a pure water rinsing step, in which the optical component is rinsed with pure water; and a drying step, in which the optical component after the cleaning solution has been washed away is dried; in the pure water rinsing step, hydrogen gas is supplied, the hydrogen gas is injected into pure water to generate hydrogen water, the hydrogen water is used to fill a clean water tank, and the oxidation-reduction potential of the hydrogen water is controlled; while the optical component is immersed in the hydrogen water in the clean water tank for rinsing, the oxidation-reduction potential of the hydrogen water is maintained at a predetermined value by the control unit.

[0018] The invention described in technical solution 9 is characterized in that, in the invention described in technical solution 8, the hydrogen gas introduced during the generation of the hydrogen water is 2.6 to 4.0 L / min / 30 L of pure water.

[0019] The invention described in technical solution 10 is characterized in that, in the invention described in technical solution 8, the pure water rinsing unit has a pH adjustment unit for replenishing an alkaline aqueous solution in order to adjust the pH of the hydrogen water.

[0020] The invention described in technical solution 11 is characterized in that, in the invention described in technical solution 8, the hydrogen water used in the water purification tank for a predetermined time is filtered and returned to the hydrogen water generation unit.

[0021] The invention described in technical solution 12 is characterized in that, in the invention described in technical solution 8, the supply of hydrogen is carried out by the electrolysis of water.

[0022] The invention described in technical solution 13 is characterized in that, in the invention described in technical solution 8, the redox potential of the hydrogen water is -400 to 0 mV.

[0023] The invention described in technical solution 14 is characterized in that, in the invention described in technical solution 10, the pH of the hydrogen water is 6.5 to 9.0.

[0024] Invention Effects The cleaning system and method for optical components according to the present invention, by dissolving hydrogen in pure water to form hydrogen water, can suppress latent damage to soft glass materials during the pure water rinsing process, thereby automating the cleaning process without manual operation. Furthermore, by controlling the redox potential and pH of the hydrogen water within a specified range, the cleaning quality after drying can be improved, resulting in a surface property where particles are difficult to adhere to. Attached Figure Description

[0025] Figure 1 This is a flowchart illustrating the cleaning system and method for the optical components of the present invention.

[0026] Figure 2 This is a schematic diagram illustrating a first embodiment of the cleaning system and method for optical components of the present invention.

[0027] Figure 3 This is a schematic diagram illustrating a second embodiment of the cleaning system and method for optical components of the present invention.

[0028] Figure 4 This is a schematic diagram illustrating a third embodiment of the cleaning system and method for optical components of the present invention.

[0029] Figure 5 This is a schematic diagram illustrating a fourth embodiment of the cleaning system and method for optical components of the present invention.

[0030] Figure 6 This is a schematic diagram illustrating a fifth embodiment of the cleaning system and method for optical components of the present invention.

[0031] Figure 7 This is a schematic diagram illustrating the details of the pure water rinsing process in the cleaning system and method for the optical components of the present invention.

[0032] Figure 8 This is a schematic diagram illustrating the details of the pure water rinsing process in the cleaning system and method for the optical components of the present invention.

[0033] Figure 9This is a graph showing the relationship between hydrogen bubbling time and hydrogen concentration and redox potential (ORP) in the examples.

[0034] Explanation of reference numerals in the attached figures S10: Cleaning process; S20: Tap water rinsing process; S30: Pure water rinsing process; S40: Drying process; A1~A2: Cleaning tank; B1~B2: Clean water tank (tap water); B1'~B3': Clean water tank (pure water); C1~4: Drying tank; L: Optical component (lens); 1: Hydrogen supply unit; 10: Electrolysis device; 11: Spacer wall; 12: Anode; 13: Cathode; 2: Hydrogen water generation unit; 20: Pure water generation section; 21: Hydrogen water generation section; 3: Clean water tank; 40: Pure water supply piping; 41: Hydrogen supply piping; 42: Hydrogen water supply piping; 43: Hydrogen water circulation piping; 44, 45: Conveying piping; 46: Drainage piping; 5: Filtration unit. Detailed Implementation

[0035] The following is a reference to the appendix. Figure 1 The specific embodiments of the cleaning system and method for the optical components of the present invention will be described below.

[0036] (First Implementation) Figure 1 This is a flowchart illustrating the basic structure of the cleaning system and method for the optical components of the present invention. Additionally, Figure 2 This is a schematic diagram of the first embodiment corresponding to the flowchart. In the following embodiments, although the illustrations are omitted, the objects to be cleaned are optical components such as lenses, which are made by cutting and grinding soft glass materials that are prone to latent damage. Furthermore, the optical components are held in metal mesh baskets (not shown) and sequentially transported within each tank.

[0037] exist Figure 1 , Figure 2 S10 is the cleaning process. In this cleaning process S10, the optical component is immersed in a cleaning tank A1 containing a cleaning solution and ultrasonic cleaning is performed. The cleaning force of the cleaning solution and the physical force of the ultrasonic waves remove and wash away fine glass powder, polishing fluid, dust, fingerprints, and other grease stains adhering to the surface of the optical component. As the cleaning agent, a cleaning agent that does not cause latent damage to soft glass materials is selected, such as a pre-evaporation cleaning solution manufactured by Yuka Kogyo Co., Ltd. The cleaning is performed at a temperature of room temperature (25°C) to 60°C, an ultrasonic cleaning output power of 0 to 1000 W, and a frequency of 28 to 1600 kHz.

[0038] S20 is a tap water rinsing process. In this tap water rinsing process S20, the optical component is immersed in a cleaning tank B1 containing tap water, and the cleaning solution components brought in from the previous process S10 are rinsed off by the tap water. Since tap water contains various dissolved ions and impurities, its effect on dissolving the metallic components contained in the soft glass material is minimal. Therefore, the cleaning solution residue on the surface can be rinsed off without causing potential damage to the soft glass material. The tap water used is readily available and can be used directly without filtration or other treatment.

[0039] S30 is a pure water rinsing process. Since pure water contains very few dissolved components, it is highly effective at dissolving the metallic components contained in soft glass materials, which has historically been a cause of latent damage. In the pure water rinsing process S30 of this invention, hydrogen water (containing trace amounts of hydrogen dissolved in pure water) is used to rinse away the cleaning solution components and tap water dissolved components brought in during the previous processes S10 and S20 that adhered to the optical components. Specifically, hydrogen water refers to water with a high hydrogen solubility.

[0040] In Figure 2 The enlarged view of the part enclosed by the dotted line, which is the pure water rinsing process S30, is shown in [the image]. Figure 7 As shown. Figure 2 , Figure 7 As shown, the pure water rinsing process S30 includes a hydrogen supply unit 1 for supplying hydrogen, a hydrogen water generation unit 2 connected to the downstream side via a hydrogen supply pipe 41, and a clean water tank 3 (=B1') connected to the downstream side via a hydrogen water supply pipe 42.

[0041] In one example, the hydrogen supply unit 1 can be an electrolysis device 10. Pure water is supplied to the electrolysis device 10 via a pure water supply pipe 40. An anode 12 and a cathode 13 are immersed in a space separated by a partition wall 11. A predetermined voltage is applied to the two electrodes, thereby electrolyzing the water to produce hydrogen and oxygen. The oxygen is released into the atmosphere or used for other purposes, while the hydrogen is transported to the hydrogen-water generation unit 2 via a hydrogen supply pipe 41. Alternatively, a hydrogen cylinder filled with hydrogen can also be used as the hydrogen supply unit 1.

[0042] The hydrogen-water generation unit 2 includes a pure water generation section 20 for supplying pure water and a hydrogen-water generation section 21 for generating hydrogen-water by combining hydrogen supplied from the hydrogen supply unit 1 with pure water. The pure water generation section 20 can utilize a known pure water production apparatus that filters tap water and performs adsorption or ion exchange of dissolved components. The hydrogen-water generation section 21 can also perform hydrogen foaming. The hydrogen-water mixture, in which hydrogen is dissolved in pure water, is transported to the purified water tank 3 via a hydrogen-water supply pipe 42. The preferred hydrogen supply rate is 2.6–4.0 L / min for 30 L of pure water. Adjustment of the hydrogen supply rate is made by adjusting the power supplied in electrolysis and by adjusting the valve opening in the case of a hydrogen cylinder.

[0043] In the purification tank 3, optical components L, such as metal mesh baskets, are immersed in hydrogen water for cleaning. A drain pipe 46 is connected to the purification tank 3, through which excess hydrogen water is discharged, so that the amount of hydrogen water in the purification tank 3 is kept constant.

[0044] Although the illustrations are omitted, the pure water rinsing process S30 of the present invention includes a control unit for controlling the redox potential of the hydrogen water. The redox potential control unit can be located either within the hydrogen water generation unit 2 or within the purified water tank 3, or it can be independently located externally. The redox potential control unit measures the redox potential of the hydrogen water at any location within the pure water rinsing process S30. The redox potential needs to be maintained below 0 mV to prevent latent damage to soft glass materials. In the present invention, as described in the embodiments, cleaning can be performed at -400 to 0 mV depending on the foaming time. Particularly preferred is below -200 mV. If the redox potential increases to a range exceeding the specified range, a control signal is fed back to the hydrogen supply unit 1 to increase the hydrogen supply.

[0045] S40 is the drying process. The optical component L is placed in the drying tank C1, and the hydrogen water remaining on the surface of the optical component is dried by rotation. Thus, the cleaning of the optical component is completed.

[0046] (Second Implementation) Figure 3 and Figure 8 The diagram shows a cleaning system and method for optical components according to a second embodiment of the present invention. Hereinafter, only the structure modified from the first embodiment will be described; descriptions of identical structures will be omitted. In the second embodiment, instead of the hydrogen-water drainage pipe 46 of the first embodiment, a hydrogen-water circulation pipe 43 is provided to return used hydrogen-water from the purification tank 3 to the hydrogen-water generation unit 2. A filter unit 5 is provided along the hydrogen-water circulation pipe 43.

[0047] The filtration unit 5 includes an adsorbent material or ion exchange resin for removing contaminants from the used hydrogen water and a pump unit for discharging the hydrogen water. Through the hydrogen water circulation piping 43 and the filtration unit 5, the used hydrogen water is returned to the hydrogen water generation unit 2, where it is again injected with hydrogen gas via the hydrogen water generation section 21 and used for cleaning. According to this embodiment, the hydrogen water can be effectively utilized without being wasted. Furthermore, because the amount of hydrogen gas consumed in the purification tank 3, the amount of hydrogen gas adsorbed in the filtration unit 5, and the amount of hydrogen gas released into the atmosphere are all very small, the original concentration can be quickly restored by returning the hydrogen water to the hydrogen water generation unit 2 and receiving hydrogen gas injection.

[0048] (Third implementation method) Figure 4 The diagram shows a schematic of a cleaning system and method for optical components according to a third embodiment of the present invention. In this embodiment, a cleaning process S10 is constituted by multiple cleaning tanks A1 and A2, and a tap water rinsing process S20 is constituted by multiple clean water tanks B1 and B2. By adopting this structure, even if cleaning is insufficient in cleaning tank A1, cleaning can be repeated in cleaning tank A2. In addition, most of the stains can be washed away in cleaning tank A1, reducing the amount of stains brought into cleaning tank A2. Furthermore, since most of the cleaning liquid and stains can be rinsed in clean water tank B1 and a final rinse is performed in clean water tank B2, the amount of cleaning liquid and stains brought into the pure water rinsing process S30 can be reduced.

[0049] In the pure water rinsing process S30, multiple clean water tanks B1', B2', and B3' are also used. In addition, the hydrogen water generation unit 2 and the clean water tank B3' are connected by a hydrogen water supply pipe 42, the clean water tanks B3' and B2' are connected by a delivery pipe 44, the clean water tanks B2' and B1' are connected by a delivery pipe 45, and the clean water tank B1' and the hydrogen water supply unit 2 are connected by a hydrogen water circulation pipe 43 and a filtration unit 5. Thus, the flow of hydrogen water is configured as a closed loop with unidirectional flow in the order of hydrogen water supply unit 2, clean water tanks B3', B2', B1', and hydrogen water supply unit 2.

[0050] According to this structure, even if the initially supplied hydrogen water contains trace amounts of contaminants when used in the highest-cleanliness water purification tank B3', it can be directly reused because the cleanliness level in the next-stage water purification tank B2' is relatively low. Similarly, even if the hydrogen water still contains contaminants when used in water purification tank B2', it can be directly reused because the cleanliness level in water purification tank B1' is the lowest.

[0051] (Fourth Implementation) Figure 5 The diagram shows a schematic of a cleaning system and method for optical components according to a fourth embodiment of the present invention. In this embodiment, water tanks B1', B2', and B3' are directly connected to the hydrogen water supply unit 2 via hydrogen water supply pipes 42a, 42b, and 42c, respectively.

[0052] (Fifth implementation method) Figure 6The diagram shows a schematic of a cleaning system and method for optical components according to a fifth embodiment of the present invention. In this embodiment, in the drying step S40, drying using isopropanol (IPA) is performed instead of the rotary drying tank C1. The optical component, having completed its final rinse in the purified water tank B3' after the final stage of the pure water rinsing step S30, is placed in the drying tank C1, where the hydrogen water adhering to the optical component is replaced with IPA. Replacement with IPA is performed each time the component is transferred to the drying tanks C1, C2, and C3, resulting in almost complete elimination of pure water content. Finally, the IPA evaporates in the drying tank C4, completing the cleaning of the optical component.

[0053] (Sixth Implementation Method) Although the illustrations are omitted, the pure water rinsing process S30 of the present invention preferably includes a hydrogen water pH adjustment unit in addition to the hydrogen water redox potential control unit. The pH adjustment unit can be installed either inside the hydrogen water generation unit 2 or the purified water tank 3, or it can be installed independently externally. The pH adjustment unit measures the pH of the hydrogen water at any location in the pure water rinsing process S30. The pH needs to be maintained between 6.5 and 9.0, preferably between 7.0 and 7.5. If the pH is more acidic than 6.5, alkali metal ions will dissolve from the soft glass material, causing latent damage. If the pH is more alkaline than 9.0, the optical component itself will dissolve. When the pH is acidic, alkaline electrolyzed water is added to adjust the pH to the specified range. Preferably, the alkaline electrolyzed water is an alkaline aqueous solution with a hydroxide concentration of less than 1% by mass obtained by electrolyzing Na salts, K salts, etc.

[0054]

Example

[0055] (Example 1) Hydrogen gas was bubbled at a rate of 2600 cc / min in 30 L of pure water (resistivity: 18 MΩ / cm). The relationship between elapsed time (minutes) and hydrogen concentration (mg / L) and redox potential (ORP, mV) was investigated. This operation was performed twice, and the results are as follows: Figure 9 As shown in the chart. Figure 9 As shown, after 60 minutes, the hydrogen concentration reaches approximately 0.2 mg / L, and the ORP reaches -150 to -250 mV. In practice, it is preferable to operate within this range. However, if foaming continues further, although the diagram is omitted, the ORP reaches -400 mV after approximately 90 minutes.

[0056] (Example 2) Because soft glass materials have poor chemical resistance, alkali metal ions contained in the glass material dissolve into pure water with an acidic pH, thus causing latent damage. To confirm this, experiments were conducted to investigate the possibility that the dissolution of these ions is suppressed in near-neutral pure water obtained by dissolving hydrogen gas, which has reducing properties.

[0057] To prevent potential latent damage, purified water with increased purity (resistance value: 18MΩ / cm) was prepared and designated as rinsing water sample No. 1.

[0058] Compared to No. 1 pure water, such as Figure 9 As shown, hydrogen gas was bubbled and dissolved for 60 minutes to prepare hydrogen water with a redox potential of -200mV (pH 7.0) and designated as No. 2.

[0059] Alkaline electrolysis with pH 12.6 was added to hydrogen water No.2 to prepare hydrogen water with pH adjusted to 7-7.5, which was designated as No.3.

[0060] Soft glass materials (models S-FPL51, S-FPL53, and S-FPL55, all manufactured by OHARA Corporation, ordered by the lowest alkali metal content) were immersed in rinsing water samples No. 1 to No. 3, and ultrasonic cleaning was performed at 25°C (room temperature), 600W output power, 40kHz frequency, and 6 minutes. After removing and drying the soft glass materials, the haze value (Hz, ambiguity value) was measured using a haze meter. The degree of latent damage to the soft glass materials was evaluated by setting 0: Hz < 0.5, Δ: 0.5 ≤ Hz < 1.0, and ×: Hz ≥ 1.0. The results are shown in Table 1.

[0061] Table 1

[0062] As the results show, hydrogen-rich water (No. 2, containing only hydrogen) exhibits a latent damage inhibition effect on all materials except S-FPL55, which is most prone to latent damage. Furthermore, hydrogen-rich water (No. 3, where alkaline electrolysis was used to adjust the pH from acidic to neutral), shows a latent damage inhibition effect on all soft glass materials. On the other hand, pure water (No. 1) caused latent damage on all soft glass materials.

[0063] Industrial applicability In cleaning systems for optical components of ophthalmic devices that are made of delicate, soft glass materials prone to latent damage, automation can be achieved without manual operation.

Claims

1. A cleaning system for cleaning optical components made of soft glass material, characterized in that, have: The cleaning unit immerses the optical components in a cleaning solution for ultrasonic cleaning. The tap water rinsing unit rinses the optical components with tap water. A pure water rinsing unit is used to rinse the optical components with pure water. The drying unit dries the optical components from which the cleaning solution has been washed away; The pure water rinsing unit has: The hydrogen supply unit supplies hydrogen. The hydrogen water generation unit injects hydrogen gas into pure water to generate hydrogen water. A purification tank, filled with the hydrogen water, and The control unit controls the redox potential of the hydrogen-water mixture; While rinsing the optical components in hydrogen water in a purification tank, the control unit maintains the oxidation-reduction potential of the hydrogen water at a specified value.

2. The cleaning system according to claim 1, characterized in that, The hydrogen gas supplied to the hydrogen-water generation unit is 2.6 to 4.0 L / min / 30 L of pure water.

3. The cleaning system according to claim 1, characterized in that, The pure water rinsing unit has a pH adjustment unit that replenishes an alkaline aqueous solution to adjust the pH of the hydrogen water.

4. The cleaning system according to claim 1, characterized in that, It includes: a hydrogen water circulation unit that returns hydrogen water used in the water purification tank to the hydrogen water generation unit at predetermined times; and a filtration unit disposed along the route of the hydrogen water circulation unit.

5. The cleaning system according to claim 1, characterized in that, The hydrogen supply unit is a water electrolysis device.

6. The cleaning system according to claim 1, characterized in that, The redox potential of the hydrogen water is -400 to 0 mV.

7. The cleaning system according to claim 3, characterized in that, The pH of the hydrogen water is 6.5 to 9.

0.

8. A cleaning method for cleaning optical components made of soft glass material, characterized in that, have: In the cleaning process, the optical components are immersed in a cleaning solution for ultrasonic cleaning. The tap water rinsing process involves rinsing the optical components with tap water. The pure water rinsing process involves rinsing the optical components with pure water, and... The drying process involves drying the optical components from which the cleaning solution has been removed. In the pure water rinsing process, Supply hydrogen, Hydrogen gas is injected into pure water to generate hydrogen water. The purified water tank is filled with the hydrogen water, and Controlling the redox potential of the hydrogen-water mixture; While rinsing the optical components in hydrogen water in a purification tank, the control unit maintains the oxidation-reduction potential of the hydrogen water at a specified value.

9. The cleaning method according to claim 8, characterized in that, The hydrogen gas introduced during the generation of the hydrogen water is 2.6 to 4.0 L / min / 30 L of pure water.

10. The cleaning method according to claim 8, characterized in that, The pure water rinsing unit has a pH adjustment unit that replenishes an alkaline aqueous solution to adjust the pH of the hydrogen water.

11. The cleaning method according to claim 8, characterized in that, The hydrogen water used in the water purification tank for a specified period of time is filtered and returned to the hydrogen water generation unit.

12. The cleaning method according to claim 8, characterized in that, The hydrogen is supplied through the electrolysis of water.

13. The cleaning method according to claim 8, characterized in that, The redox potential of the hydrogen water is -400 to 0 mV.

14. The cleaning method according to claim 10, characterized in that, The pH of the hydrogen water is 6.5 to 9.0.

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