Optical article with electrochromic cell

Abstract

Optical article (10) comprising: - a bottom connecting structure (100); - an EC core layer (20) placed on the bottom connecting structure (100); and - a top connecting structure (200) placed on the EC core layer (20); wherein at an end of the optical article (10), the bottom connecting structure (100) and the top connecting structure (200) extend laterally outward with respect to a lateral side (26) of the optical article (10), thus forming a respective bottom protrusion (28a) and top protrusion (28b), so as to allow connection with a flex connector (30).

Description

OPTICAL ARTICLE WITH ELECTROCHROMIC CELLDESCRIPTIONTechnical field

[0001] This invention relates to an optical article with electrochromic cell.information and art

[0002] Optical articles which employ an electrochromic (“EC” in the following) cell connected to a processing circuit fixed to a frame are known. Said cells usually comprise a first transparent layer on the front face which has a curvature corresponding to the curvature of a frame and a second transparent layer on the rear face so that such first and second layers define a cavity between them. The cavity is closed and filled with an electrochromic solution and is connected to the processing circuit to control an optical amplitude of the EC cell.

[0003] The cell is connected to the processing circuit via a connection element. Solutions for performing such a connection exist, which use spring contacts or Pogo pins directly on a metallic layer of the EC cell.

[0004] These solutions have several drawbacks:- springs contacts or Pogo pins are mechanically held by the frame, and this leads to limitations on the frame design;- the EC cell interface with the frame may require a soft material for mechanical protection of the EC cell, and therefore the positioning could not be accurate enough to use a spring contact or a Pogo pin; and- the EC cell has metallized areas on two opposite sides, this making the overall design even more complex.

[0005] Accordingly, there is the need to provide an innovative optical article with electrochromic cell which allows a simple and robust connection with a processing circuit, thus overcoming the problems of the prior art.

[0006] What is provided herein is an optical article comprising:- a bottom connecting structure;- an EC core layer placed on the bottom connecting structure; and- a top connecting structure placed on the EC core layer;wherein at an end of the optical article, the bottom connecting structure and the top connecting structure extend laterally outward with respect to a lateral side of the optical article, thus forming a respective bottom protrusion and top protrusion, so as to allow connection with a flex connector.

[0007] In an embodiment, the optical article further comprises a support layer and an adhesive layer placed on the support layer, the bottom connecting structure being placed on the adhesive layer.

[0008] In an embodiment, each protrusion has a thickness equal to that of a flex PCB.

[0009] In an embodiment, the top protrusion has, on a side thereof, a top recessed portion having an L-shaped outline and the bottom protrusion has, on a side thereof facing opposite to side of the top protrusion, a bottom recessed portion having an L-shaped outline; the L-shaped outline of the top recessed portion having a longer side and a shorter side, the L-shaped outline of the bottom recessed portion having a longer side and a shorter side, wherein the longer side of the L-shaped outline of the top recessed portion is parallel to the longer side of the L-shaped outline of the bottom recessed portion and the respective shorter sides extends in opposite directions.

[0010] In an embodiment, the bottom connecting structure comprises a bottom PET layer and a bottom conductive layer placed on the bottom PET layer.

[0011] In an embodiment, the optical article further comprises a bottom metallic layer placed on the bottom conductive layer and surrounding the EC core layer.

[0012] In an embodiment, the top connecting structure comprises a top conductive layer placed on the EC core layer and a top PET layer placed on the top conductive layer.

[0013] In an embodiment, the optical article further comprises a top metallic layer placed in contact with the top conductive layer and surrounding the EC core layer.

[0014] In an embodiment, the bottom conductive layer comprises a tin-doped indium oxide layer.

[0015] In an embodiment, the top conductive layer comprises a tin-doped indium oxide layer.

[0016] In an embodiment, the bottom metallic layer comprises an Ag layer.

[0017] In an embodiment, the top metallic layer comprises an Ag layer.

[0018] In an embodiment, the optical article further comprises a glue layer placed between the two metallic layers and surrounding the EC core layer.

[0019] In an embodiment, the bottom protrusion and top protrusion have a respective thickness of 200pm.

[0020] In an embodiment, the bottom metallic layer (22a) and bottom conductive layer (18a), and the top metallic layer (22b) and top conductive layer (18b) have a respective thickness of 25pm.Description of the drawings

[0021] Further characteristics and advantages of the present invention will become apparent from the following description, provided merely by way of a non-limiting example, with reference to the attached drawings, in which:

[0022] Figure 1 shows a cross-section of an optical article according to the present invention;

[0023] Figure 2 shows a perspective view of the optical article of Figure 1 ;

[0024] Figure 3 is a plan view of the optical article of Figure 1 ; and

[0025] Figure 4 is an enlarged picture of a portion of the optical article of Figure 2.Detailed description of embodiments

[0026] In the description which follows, the drawing figures are not necessarily to scale, and certain features may be shown in generalized or schematic form in the interest of clarity and conciseness or for informational purposes. Embodiments discussed herein are merely representative and do not limit the scope of the invention. It will also be obvious to one skilled in the art that all the technical features that are defined relative to a process can be transposed, individually or in combination, to a device and conversely, all the technical features relative to a device can be transposed, individually or in combination, to a process. To avoid unnecessary details for practicing the invention, the description may omit certain information already known to those skilled in the art.

[0027] The optical article of the present invention can be directly connected to an existing connector thanks to protrusions made of layers surrounding an EC cell. The connector is in turnarranged to be connected to a control circuit, for example a miniaturized electronic control board equipped with a microcontroller, which can be used to control the EC cell in a known manner.

[0028] Figure 1 shows a cross-section of an optical article according to the present invention.

[0029] An optical article 10 comprises a support layer 12, for example a lens, a wafer or a film.

[0030] On top of the support layer 12, an adhesive layer 14, for example a PSA (Pressure sensitive Adhesive) layer or a liquid optical glue, is placed.

[0031] On top of the adhesive layer 14, firstly a bottom PET (or, more generally, any other suitable transparent polymer) layer 16a and secondly a bottom conductive layer 18a, for example a tin-doped indium oxide layer, are placed. Then, an EC core layer 20 is placed on the bottom conductive layer 18a and is preferably surrounded by a bottom metallic layer 22a (see also Figure 2), for example an Ag layer, which is deposited on the bottom conductive layer 18a around the contour of the EC core layer 20.

[0032] On top of the EC core layer 20 a top conductive layer 18b, for example a tin-doped indium oxide layer, and a top PET (or, more generally, any other suitable transparent polymer) layer 16b are placed, one after the other. Preferably, a top metallic layer 22b, for example an Ag layer, is placed in contact with the top conductive layer 18b, surrounding the EC core layer 20 similarly to the bottom metallic layer 22a.

[0033] Finally, a glue layer 24 is placed between the two metallic layers 22a, 22b, surrounding the EC core layer 20.

[0034] The bottom metallic layer 22a, the bottom conductive layer 18a and the bottom PET layer 16a represent altogether a bottom connecting structure 100.

[0035] The top metallic layer 22b, the top conductive layer 18b and the top PET layer 16b represent altogether a top connecting structure 200.

[0036] The bottom connecting structure 100, the top connecting structure 200 and the EC core layer 20 represent altogether an EC cell.

[0037] The bottom and top PET layers 16a, 16b have advantageously a respective thickness of 175pm, while the two metallic layers 22a, 22b and respective bottom and top conductive layer 18a, 18b have a respective thickness of 25pm. The two metallic layers 22a, 22b, are placed around the EC core layer 20 to have a uniformity in electrical potential of the respective bottom and top conductive layer 18a, 18b.

[0038] At an end of the optical article 10, the top connecting structure 200 and the bottom connecting structure 100 extend laterally outward with respect to a lateral side 26 of the optical article 10, thus forming a respective bottom protrusion 28a and top protrusion 28b.

[0039] The bottom protrusion 28a and top protrusion 28b have advantageously a respective thickness of 200pm.

[0040] Figure 2 shows a perspective view of the optical 10 of Figure 1 , while Figure 3 is a plan view of said optical article 10.

[0041] In Figure 3, the protrusions 28a, 28b are connected to a standard flex connector 30.

[0042] The flex connector 30 is in turn arranged to be connected to a processing circuit to control an optical amplitude of the EC core layer 20, as above disclosed.

[0043] Each protrusion 28a, 28b has a thickness equal to that of a flex PCB, so, it is possible to use a standard commercial flex connector 30 for connecting the optical article 10 to the processing circuit, thus simplifying the connection of the optical article 10 by using a robust connection mechanism with the processing circuit.

[0044] Each protrusion 28a, 28b has also a shape which is compatible with the one of the flex connector 30, as below detailed.

[0045] The flex connector 30 is a double-side connector and this solves the recurring problem of connecting an optical article which has two metallic layers placed on opposite sides.

[0046] The optical article 10 of the present invention has been tested for example with connector Hirose FH587 points.

[0047] As above indicated, the shape of the protrusions 28a, 28b is suitable for coupling the optical article 10 with the flex connector 30, as shown in Figure 4, which is an enlarged picture of the portion of the optical 10 wherein the protrusions 28a, 28b are formed.

[0048] The top protrusion 28b has, on a side thereof, a top recessed portion 32 having an L-shaped outline.

[0049] The bottom protrusion 28a has, on a side thereof facing opposite to the above-mentioned side of the top protrusion 28b, a bottom recessed portion 34 having an L-shaped outline.

[0050] The L-shaped outline of the top recessed portion 32 has a longer side 32a and a shorter side 32b.

[0051] The L-shaped outline of the bottom recessed portion 34 has a longer side 34a and a shorter side 34b.

[0052] The longer side 32a of the L-shaped outline of the top recessed portion 32 is parallel to the longer side 34a of the L-shaped outline of the bottom recessed portion 34, while the respective shorter sides 32b, 34b extends in opposite directions.

[0053] Thanks to the symmetrical orientation of the recessed portions 32, 34, the protrusions 28a, 28b can be inserted in the flex connector 30.

[0054] Alternatively, other shapes of the recessed portions 32, 34 can be obtained, by cutting the respective protrusion 28a, 28b along cut lines having different shapes.

[0055] The cutting of the protrusions 28a, 28b can be done after assembly the optical article 10 with a laser cutting machine. It could also be realized by stamping with a metallic tool.

[0056] Advantageously, the cut is realized before assembly the bottom and top connecting structures 100, 200, to avoid managing an too extended cutting depth.

[0057] Clearly, the principle of the invention remaining the same, the embodiments and details of production can be varied considerably from what has been described and illustrated purely by way of non-limiting example, without departing from the scope of protection of the present as defined in the attached claims.

Claims

CLAIMS1. Optical article (10) comprising:- a bottom connecting structure (100);- an EC core layer (20) placed on the bottom connecting structure (100); and- a top connecting structure (200) placed on the EC core layer (20);wherein at an end of the optical article (10), the bottom connecting structure (100) and the top connecting structure (200) extend laterally outward with respect to a lateral side (26) of the optical article (10), thus forming a respective bottom protrusion (28a) and top protrusion (28b), so as to allow connection with a flex connector (30);characterized in that:- the top protrusion (28b) has, on a side thereof, a top recessed portion (32) having an L-shaped outline;- the bottom protrusion (28a) has, on a side thereof facing opposite to side of the top protrusion (28a), a bottom recessed portion (34) having an L-shaped outline;the L-shaped outline of the top recessed portion (32) having a longer side (32a) and a shorter side (32b), the L-shaped outline of the bottom recessed portion (34) having a longer side (34a) and a shorter side (34b), wherein the longer side (32a) of the L-shaped outline of the top recessed portion (32) is parallel to the longer side (34a) of the L-shaped outline of the bottom recessed portion (34) and the respective shorter sides (32b, 34b) extends in opposite directions...

2. The optical article of claim 1 , further comprising- a support layer (12);- an adhesive layer (14) placed on the support layer (12);the bottom connecting structure (100) being placed on the adhesive layer (14).

3. The optical article of claims 1 or 2, wherein each protrusion (28a, 28b) has a thickness equal to that of a flex PCB.

4. The optical article of any of the above claims, wherein the bottom connecting structure (100) comprises a bottom PET layer (16a) and a bottom conductive layer (18a) placed on the bottom PET layer (16a).

5. The optical article of claim 4, further comprising a bottom metallic layer (22a) placed on the bottom conductive layer (18a) and surrounding the EC core layer (20).

6. The optical article of any of the above claims, wherein the top connecting structure (200) comprises a top conductive layer (18b) placed on the EC core layer (20) and a top PET layer (16b) placed on the top conductive layer (18b).

7. The optical article of claim 6, further comprising a top metallic layer (22b) placed in contact with the top conductive layer (18b) and surrounding the EC core layer (20).

8. The optical article of claim 4, wherein the bottom conductive layer (18a) comprises a tin-doped indium oxide layer.

9. The optical article of claim 6, wherein the top conductive layer (18b) comprises a tin-doped indium oxide layer.

10. The optical article of claim 4, wherein the bottom metallic layer (22a) comprises an Ag layer.

11. The optical article of claim 6, wherein the top metallic layer (22b) comprises an Ag layer.

12. The optical article of any of the above claims, further comprising a glue layer (24) placed between the two metallic layers (22a, 22b) and surrounding the EC core layer (20).

13. The optical article of claims 4 and 6, wherein the bottom protrusion (28a) and top protrusion (28b) have a respective thickness of 200pm.

14. The optical article of claims 5 and 7, wherein the bottom metallic layer (22a) and bottom conductive layer (18a), and the top metallic layer (22b) and top conductive layer (18b) have a respective thickness of 25pm.

Images