Eye protection device with variable transparency

Abstract

The eye protection device (1) according to the invention comprises: an at least partially transparent structural lens (3) on which at least one variable transparency liquid crystal layer (8) is applied; and a photovoltaic cell (51) for activating the liquid crystal layer, the photovoltaic cell being covered at the front by an at least partially transparent element (3, 31). Such a device is characterized in that the at least partially transparent element (3, 31) has a cover region (91) in front of the photovoltaic cell (51), which cover region (91) has a surface reflection treatment (9), while the structural lens (3) has a field of view region (90), which field of view region (90) does not have a surface reflection treatment (9) and / or which field of view region (90) has a surface reflection treatment (9), the surface reflection processing part of the visual field area has a reflection light percentage lower than the reflection light percentage of the surface reflection processing part of the coverage area (91). The device is almost invisible or completely invisible to external observers due to the presence of a surface reflective treatment covering at least the photovoltaic cells, so that the device is highly aesthetically pleasing.

Description

Technical Field

[0001] This invention relates to an eye protection device that can change its transparency according to the usage and has a high aesthetic effect. Background Technology

[0002] In many situations, especially outdoors, it is essential to protect the eyes from particulate matter, wind, ultraviolet radiation, excessive sunlight, and other harmful substances. While mechanical and UV protection are largely easy to implement, protection against excessive sunlight exposure for visible light radiation is more complex because the optimal level of protection varies depending on the individual user.

[0003] Therefore, five types of solar filters have been introduced at the regulatory level, each suitable for specific situations. However, carrying five different pairs of glasses or lenses and changing them as needed is clearly impractical.

[0004] Therefore, photochromic lenses were developed. These lenses reduce the transmittance of ultraviolet light through a chemical reaction. However, these lenses also have some drawbacks: the reaction speed is very slow, they mainly react with ultraviolet light rather than visible light, and they are highly susceptible to temperature changes.

[0005] Electrochromic lenses have also been developed, which can change their light transmittance through electronic control. While these lenses are faster than photochromic lenses, they are still quite slow. Furthermore, these lenses require control to change their state, and each state change involves considerable energy consumption. Therefore, electrochromic lenses require a power source battery, which, when integrated into a typical protective device such as a pair of classic sunglasses, results in a bulky and heavy battery.

[0006] Finally, liquid crystal lenses were developed that change their transmittance most rapidly. US Patent document US 6,433,913 illustrates an example of protective liquid crystal glasses. Several liquid crystal lens solutions have proven effective in compensating for sudden changes in light that users frequently encounter in daily life or specific activities. For example, the applicant has filed patent application WO2023047271A1 related to GH liquid crystal protective glasses.

[0007] Combining a liquid crystal lens with a photovoltaic cell is highly effective, eliminating the need for a dedicated power source. It should be noted that the photovoltaic cell, in addition to serving as a power source, can also function as a sensor for activating the lens. Alternatively, the photovoltaic cell can be used solely as a power source, with a separate sensor for activating the lens.

[0008] Generally, optimal liquid crystal lens solutions using photovoltaic cells as a power source require relatively large solar cells, with a surface area of ​​approximately several square centimeters. It is precisely because of the size of these cells that they can even significantly impact the appearance of protective equipment, severely limiting public acceptance of this new technology, especially in devices designed for everyday wear. In fact, to attract a wider audience, a classic pair of sunglasses must possess a certain aesthetic appeal. Summary of the Invention

[0009] The purpose of this invention is to provide a variable transparency type eye protection device that is always effective under any usage conditions, wherein the presence of photovoltaic cells is almost invisible or completely invisible to external observers, thereby achieving a high aesthetic effect.

[0010] This objective is achieved by the protective device according to claim 1. The dependent claims disclose other advantageous embodiments of the invention. Attached Figure Description

[0011] The features and advantages of the protective device according to the invention will become apparent from the following description of non-limiting examples given in conjunction with the accompanying drawings, in which: Figure 1 An eye protection device with variable transparency according to the present invention is shown, the eye protection device being constructed as sunglasses; Figure 2 It shows Figure 1 Exploded view of the central protection device; Figure 3 It shows Figure 1 A top view of the protective device in the image, with section AA highlighted; Figure 4 It shows Figure 1 The cross-sectional view and enlarged view of the protective device along the AA plane; Figure 5 A front view of the eye protection device with variable transparency according to the present invention in use is shown. Figure 6 A series of geometric patterns (represented by letters A to F) for a surface reflective treatment portion applied to a protective device according to the present invention are shown. Figure 7 A series of embodiments of the protective device according to the present invention are shown (denoted by letters A to D); Figure 8 This is an exploded view of an eye protection device with variable transparency according to another exemplary embodiment of the present invention. Detailed Implementation

[0012] Referring to the accompanying drawings, an eye protection device with variable transparency according to the present invention, particularly eyeglasses, is shown in full by reference numeral 1.

[0013] The protective device 1 includes a frame 2 adapted to support a lens assembly 6, the lens assembly 6 including a structural lens 3, the inner side of which is coated with at least one liquid crystal layer 8 having variable transparency.

[0014] Preferably, such as Figure 1 As shown, frame 2 completely surrounds lens assembly 6.

[0015] For example, frame 2 is made of a polymer material or a polymer-based composite material. Preferably, a reinforcing material, such as glass fiber, carbon fiber, glass, or graphene microspheres, is added to the polymer-based composite material. For example, frame 2 is made of polyamide reinforced with glass fiber or carbon fiber. In alternative embodiments, frame 2 is made of a lightweight metallic material, such as an aluminum, titanium, or magnesium alloy. Depending on the selected material, frame 2 is obtained by injection molding; alternatively, frame 2 is manufactured by forging, die casting, or sheet metal forming. Advantageously, the materials listed above enable the obtaining of a frame 2 with sufficient rigidity, thereby preventing deformation of lens assembly 6 during use, which would be transmitted to liquid crystal layer 8 and affect its optical uniformity.

[0016] When the protective device 1 is constructed as eyeglasses, it includes two temples 13, each temple 13 being provided with a hinge connector 131, the hinge connector 131 allowing, for example, interlocking ( Figure 8 ) or use small screws 132 ( Figure 2 The temples 13 are assembled with the frame 2 in a manner that allows them to be stacked together when not in use, thus reducing the size of the glasses.

[0017] The structural lens 3 is assembled to the frame 2 via an interlocking bevel inside the frame 2. In an alternative example, the structural lens 3 is assembled to the frame 2 via double-sided adhesive tape (e.g., with a thickness of 0.5 mm to 3 mm). In yet another alternative example, the structural lens 3 is assembled to an interlocking frame 2 located in a slot inside the frame 2.

[0018] Preferably, the structural lens 3 is made of polyamide or polycarbonate with a thickness of 0.8 mm to 3 mm.

[0019] Preferably, the structural lens 3 has anti-reflective and / or anti-scratch and / or hydrophobic and / or oleophobic treatments.

[0020] In an exemplary embodiment, the structural lens 3 has a groove in which the photovoltaic cell 51 is partially or entirely housed.

[0021] In an exemplary embodiment, the structural lens 3 is provided with one or two photochromic films.

[0022] In an exemplary embodiment, the structural lens 3 has a pigment in order to increase contrast in a device for a particular purpose.

[0023] The frame 2 is provided with a base or recess 4, in which at least one photovoltaic cell 51 is housed. This photovoltaic cell preferably serves both as an energy source for the liquid crystal layer 8 and as a sensor for activating the liquid crystal layer 8. Preferably, the entire circuit board 5, including the photovoltaic cell 51, is housed in the base 4. The circuit board 5 is the control module for the liquid crystal layer 8. At least one liquid crystal layer 8 is connected to the circuit board 5 containing the photovoltaic cell 51 via a flexible printed circuit (FPC) 52.

[0024] Advantageously, such as Figure 2 As shown, the groove 4 is positioned at the front, top, and center of the frame 2, thus avoiding annoyingly narrowing the user's field of vision.

[0025] exist Figure 2 In the exemplary embodiment shown, the structural lens 3 is arranged such that it closes the recess 4 in front of the circuit board 5, and the rear of the circuit board 5 is protected by the wall of the recess 4 formed in the frame 2. Figure 8 In another exemplary embodiment shown, the cover 31 is configured to enclose the recess 4 in front of the circuit board 5, the rear of which is protected by the walls of the recess 4 formed in the frame 2. Advantageously, both solutions provide mechanical and chemical protection for the circuit board 5. Therefore, in Figure 2 In the example shown, the structural lens 3 also constitutes the cover of the photovoltaic cell 51; while Figure 8 In the example shown, a cover 31 separate from the structural lens 3 is used to cover the photovoltaic cell 51. Figure 2 In the example, the structural lens 3 also forms a cover for the photovoltaic cell 51. Preferably, the liquid crystal layer 8 is not disposed between the structural lens 3 and the photovoltaic cell 51.

[0026] The structural lens 3 or cover 31 (if present) is at least partially transparent so that light can reach the photovoltaic cell 51. The term "at least partially transparent" means an element that allows at least 50% of light to pass through.

[0027] Therefore, in the protective device 1, the front of the photovoltaic cell 51 is covered by at least a partially transparent element, which may be a structural lens 3 or a cover 31. In the protective device 1, the at least partially transparent element covering the photovoltaic cell 51 has a surface reflection treatment 9.

[0028] The surface reflection treatment 9 increases the percentage of light reflected from the outer surface of the structural lens 3. Preferably, the percentage of light reflected by the surface reflection treatment 9 is between 5% and 40%. Advantageously, the presence of the surface reflection treatment 9 allows the photovoltaic cell 51 to be shielded from the view of an external observer, even if no bright or light-emitting element is reflected by the at least partially transparent element.

[0029] Preferably, such as Figure 7 As shown in various exemplary embodiments, the surface reflection treatment section 9 exists only in certain areas of the surface of the at least partially transparent element.

[0030] Therefore, the protective device 1 has at least partially transparent elements 3 and 31, which have a coverage area 91 located at least partially in front of the photovoltaic cell 51. This coverage area 91 is provided with a surface reflection treatment 9 having a certain percentage of reflected light. Furthermore, the structural lens 3 has at least one field of view 90 for user observation, which does not have a surface reflection treatment (such as...). Figure 7 Examples A, B, and C are shown), and / or at least one viewing area 90 is provided with a surface reflection treatment portion, the percentage of light reflected by the surface reflection treatment portion being lower than the percentage of light reflected by the surface reflection treatment portion of the coverage area 91 (e.g., ...). Figure 7 (As shown in Example D). Advantageously, the presence of the coverage area 91 allows the photovoltaic cell 51 to be shielded from the view of an external observer while still allowing most of the light to reach the photovoltaic cell 51, thus ensuring the normal function of the liquid crystal layer 8.

[0031] In the preferred embodiment, the surface reflection treatment section 9 at least partially covers the photovoltaic cell 51, but does not cover the area in front of the user's eyes (e.g., ...). Figure 7 Examples A, B, and C in the diagram are shown. Preferably, the surface reflective treatment 9 does not cover an area with a radius R of 13 mm emanating from the projection point P of the user's pupil center in the front view (e.g., ...). Figure 5 (As shown). Advantageously, this configuration allows for the use of a highly effective surface reflective treatment to cover the photovoltaic cell 51 without compromising the optical quality of the protective device 1 in areas where proper vision is crucial for the user.

[0032] At least partially transparent elements (whether structural lens 3 or cover 31) have an inner surface facing the photovoltaic cell 51 and an outer surface facing away from it. One of these surfaces is treated with a surface reflection treatment. Preferably, the surface reflection treatment is applied to the outer surface.

[0033] Preferably, the surface reflection treatment part 9 is opaque, matte, or in any case non-mirror.

[0034] The surface reflective treatment section can be multi-layered or single-layered, and can be neutral-colored or colored (e.g., silver, gold, red, blue, green, pink, purple). For example, the surface reflective treatment section is a multi-layered treatment section with the reflectance spectrum centered on the infrared wavelength.

[0035] For example, surface reflective treatment part 9 can be superimposed on another surface reflective treatment part to enhance its intensity in certain areas. For example, such as Figure 7 As shown in embodiment variant D, a surface reflection treatment with higher intensity, located at least partially in front of the photovoltaic cell 51, is superimposed on the light-reflecting surface treatment. Advantageously, the reflection of the surface reflection treatment present at the photovoltaic cell 51 (coverage area 91) is therefore higher than the reflection of any other surface reflection treatment present in the area in front of the user's eyes (field of vision area 90), thereby blocking the photovoltaic cell without affecting the correct vision obtained through glasses.

[0036] Preferably, according to a predetermined design, the surface reflective treatment portion 9 is present on at least a portion of the surface of the transparent elements 3, 31. Preferably, the surface reflective treatment portion 9 includes either a full / empty design or pattern, wherein the surface reflective treatment portion is present in the "full" region (p) and not located in the "empty" region (v). Advantageously, the surface reflective treatment portion having a full / empty pattern further increases the amount of light that can reach the photovoltaic cell 51.

[0037] The pattern can be formed by repeating any linear, radial, square grid, triangular, or hexagonal shape of any geometric shape. Figure 6 The variant implementations marked with letters A through F show some possible examples of this pattern: - A: Dotted surface reflective treatment part, which has uniform circular dots; - B: Surface reflection treatment section, where uniform circular dots in the background of the surface reflection treatment section have not been processed; - C: Dotted surface reflective treatment section, in which the circular dots decrease to one side; - D: Dotted surface reflective treatment section, in which the hexagonal dots decrease to one side; - E: Surface reflection treatment section, in which the untreated hexagonal dots in the background of the surface reflection treatment section increase to one side; - F: Dotted surface reflective treatment section, in which the hexagonal dots decrease towards the center.

[0038] The surface reflection treatment unit 9 with a full / empty pattern is characterized in that the surface coverage is given by the ratio of the surface reflection area ("full") to the total area of ​​the coverage area 91 and is between 1 / 8 and 1 / 2.

[0039] Preferably, the coverage factor varies with the processing area. More preferably, the coverage factor varies gradually in space, with the coverage factor at the photovoltaic cell 51 being greater than the coverage factor in the area in front of the user.

[0040] As mentioned above, at least one liquid crystal layer or thin film 8 is present within the structural lens 3 in a region positioned in front of the user's eyes. In one embodiment, a single structural lens 3 is present, wherein the laminated liquid crystal layer 8 covers two regions in front of the user's eyes. In another example, a single structural lens 3 is present, wherein the laminated pairs of liquid crystal layers 8 are as follows: Figure 2 As shown. In a further implementation example, for example... Figure 7 In Example B, there are pairs of different structural lenses 3, each with its own liquid crystal layer 8; in this embodiment, there is a cover 31.

[0041] The liquid crystal layer 8 is surrounded by a peripheral seal 81, which allows the liquid crystal layer to be enclosed and sealed within a chamber composed of the two substrates and the seal. Preferably, a surface reflective treatment 9 also covers the seal 81, making the seal 81 less noticeable from the outside. Figure 5 As shown.

[0042] Preferably, the inner side of the seal is covered by the frame 2. Preferably, the frame 2 also covers any gaps between the liquid crystal layer 8 and the frame 2.

[0043] Preferably, the liquid crystal layer 8 is composed of guest-host type liquid crystal, wherein the liquid crystal matrix guides the orientation of the dichroic pigments, causing variations in the orientation of the dichroic pigments, thereby resulting in different levels of transparency. In the absence of an electric field, the pigments align perpendicularly to the substrate via a suitably formed alignment layer. In the presence of an electric field, the liquid crystal molecules and the dichroic pigments align parallel to the substrate, thereby reducing the transmittance of the liquid crystal layer.

[0044] When using a host-guest type liquid crystal layer 8, it is preferable to arrange at least one depolarizing film between the liquid crystal layer 8 and the structural lens 3. Advantageously, this configuration can eliminate interference between the internal stresses that often exist within the liquid crystal layer and the structural lens, especially when the structural lens is manufactured by injection molding.

[0045] In an alternative example, liquid crystal layer 8 is a "twisted nematic" type liquid crystal. In this type of layer, the liquid crystal exhibits birefringence, which allows a properly constructed liquid crystal to change the polarization direction of light, enabling light to pass through two non-parallel polarizing filters. In the absence of an electric field, the orientation of the liquid crystal changes, no longer guiding polarized light in this manner; therefore, the second polarizing filter almost completely blocks all light passing through the first filter.

[0046] When using a "twisted nematic" type liquid crystal layer 8, it is preferable that the two polarizing filters existing inside and outside the liquid crystal layer are not completely polarized, so that its theoretical transmittance in the inactive state is greater than 50%, and its theoretical transmittance in the activated state is significantly greater than 0%. Typically, the transmittance of the activated liquid crystal layer is between 4% and 15%.

[0047] like Figure 2 As shown, the liquid crystal layer 8 is connected to the circuit board 5 containing the photovoltaic cell 51 via a flexible printed circuit (FPC). Preferably, the surface reflective treatment portion 9 also covers the connection area between the liquid crystal layer 8 and the flexible printed circuit, making it less noticeable from the outside, such as... Figure 5 as well as Figure 7 Examples B and C are shown.

[0048] A cover 7 is preferably applied inside the structural lens 3, for example, made by transfer printing or other printing methods, and is adapted to block the bonding area between the liquid crystal layer 8 and the flexible printed circuit 52. Advantageously, this solution can further block the flexible printed circuit by a surface reflection treatment, making it invisible in a transparent state.

[0049] Preferably, the frame 2 and / or photovoltaic cell 51 and / or flexible printed circuit board 52 and / or seal 81 are dark or black. Advantageously, this technical solution further reduces the visibility of these components through a surface reflective treatment.

[0050] In other embodiments of the invention, the photovoltaic cell 51 is independent of the circuit board 5 and is connected to the circuit board 5 via a flexible printed circuit or via wires.

[0051] In other embodiments of the present invention, an activation sensor for the liquid crystal layer 8 is also provided, the size of which is smaller than the size of the photovoltaic cell 51, and the photovoltaic cell 51 is used only as a power source.

[0052] Preferably, the photovoltaic cell 51 is a monocrystalline, amorphous, organic, or other known type of solar cell. Preferably, the photovoltaic cell 51 is monocrystalline and flexible, thereby enabling it to follow the curvature of the structural lens 3 or the cover 31. For example, the monocrystalline photovoltaic cell 51 can be made from a silicon wafer with a thickness of 50 μm or less.

[0053] Preferably, the photovoltaic cell 51 is laminated to the structural lens 3 or the cover 31 using an optical adhesive.

[0054] In one example, a "photovoltaic cell" refers to a panel containing multiple solar cells arranged in series. In another example, a "photovoltaic cell" refers to multiple panels, each containing multiple solar cells arranged in series. In both examples, the total number of solar cells present is preferably 6 to 16. In one example, the panel can be obtained by assembling multiple photodiodes on a rigid or flexible circuit board 5.

[0055] Preferably, the circuit board 5 is connected to the flexible printed circuit board via a small connector or soldering.

[0056] When a pair of liquid crystal layers 8 are present, there can be two independent flexible printed circuits 52, such as... Figure 2 As shown, it may also have a single flexible printed circuit connected to the two liquid crystal layers 8.

[0057] In short, Figure 7 Some embodiments of the protective device 1 according to the present invention are shown: - A: The coverage area 91 with the surface reflection treatment part 9 exists only in front of the photovoltaic cell 51, and the viewing area 90 has no surface reflection treatment part at all; - B: There is a coverage area 91 with a surface reflection treatment part 9 in front of the photovoltaic cell 51 and in front of the connection between the liquid crystal layer 8 and the flexible printed circuit 52, while the viewing area 90 has no surface reflection treatment part at all. - C: In front of the photovoltaic cell 51, in front of the connection between the liquid crystal layer 8 and the flexible printed circuit 52, and in front of the seal 81 of the liquid crystal layer 8, there is a coverage area 91 with a surface reflection treatment part 9, while the viewing area 90 has no surface reflection treatment part at all. - D: There is a coverage area 91 with a surface reflection treatment section 9 in front of the photovoltaic cell 51, and the viewing area 90 has a surface reflection treatment section, which has a lower percentage of reflected light than the surface reflection treatment section of the coverage area 91.

[0058] Innovatively, the eye protection device according to the invention has variable transparency so as to be effective in all kinds of use conditions, and has high aesthetic appeal due to the presence of a surface reflective treatment covering at least the photovoltaic cell, which is almost invisible or completely invisible to an external observer.

[0059] It should be understood that those skilled in the art may modify the apparatus described above to meet specific needs, and all such modifications are included within the scope of protection defined by the appended claims.

Claims

1. An eye protection device (1) with variable transparency, the protection device having a frame (2) adapted to support a lens assembly (6), the protection device comprising: - At least one structural lens (3), at least one of the structural lenses is at least partially transparent, and at least one liquid crystal layer (8) with variable transparency is applied to at least one of the structural lenses. - A sensor, or at least one photovoltaic cell (51), the sensor or at least one of the photovoltaic cells being used to activate the liquid crystal layer (8), with at least partially transparent elements (3, 31) covering the front of the sensor or at least one of the photovoltaic cells (51). The feature is that the at least partially transparent element (3, 31) has a covering area (91) provided with a surface reflection treatment part (9), and the covering area is at least partially arranged in front of the photovoltaic cell (51); as well as The structural lens (3) has at least one field of view (90) for the user to view, the at least one field of view having no surface reflection treatment (9), and / or the at least one field of view having a surface reflection treatment, the surface reflection treatment of the field of view having a lower percentage of reflected light than the surface reflection treatment of the covered area (91).

2. The protection device (1) according to claim 1, wherein, The at least partially transparent element is: - At least one of the structural lenses (3), or - A cover (31) that is different from the structure lens (3).

3. The protection device (1) according to claim 1 or 2, wherein, The photovoltaic cell (51) serves both as a sensor for activating the liquid crystal layer (8) and as an energy source for supplying power to the liquid crystal layer (8).

4. The protective device (1) according to any one of the preceding claims, wherein, The surface reflection treatment part (9) has a smooth, opaque or non-mirror reflective part.

5. The protective device (1) according to any one of the preceding claims, wherein, The at least partially transparent element is a structural lens (3) having two viewing areas (90) without the surface reflection treatment (9), each viewing area occupying a circle with a radius of at least 13 mm.

6. The protective device (1) according to any one of the preceding claims, wherein, The at least one liquid crystal layer (8) is provided with a peripheral seal (81), and the coverage area (91) where the surface reflection treatment part (9) is provided also covers the peripheral seal (81).

7. The protective device (1) according to any one of the preceding claims, wherein, The surface reflection processing unit (9) includes a full / empty pattern, in which surface reflection exists in the "full" area and not in the "empty" area.

8. The protection device (1) according to claim 7, wherein, In the pattern, the ratio of "full" to total surface area in the covered area (91) is between 1 / 8 and 1 / 2.

9. The protective device (1) according to any one of the preceding claims, wherein, At least one of the liquid crystal layers (8) has a guest-host type.

10. The protection device (1) according to claim 9, wherein, A depolarization layer exists between at least one of the liquid crystal layers (8) and at least one of the structural lenses (3).

11. The protective device (1) according to any one of the preceding claims, wherein, The photovoltaic cell (51) includes a semi-flexible monocrystalline photovoltaic panel that follows the curvature of the structural lens (3).

Images