Eye movement tracking FPC structure and rimless glasses
By using a transparent substrate and a grid-like copper wire layer design in the eye-tracking FPC structure, the infrared LED bare chip is brought closer to the eyeball, solving the problems of small field of view and high cost, and achieving a larger field of view and lower cost eye-tracking effect.
Patent Information
- Application Number
- CN202422692436.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-05
- Publication Date
- 2025-12-19
- Estimated Expiration
- 2034-11-05
AI Technical Summary
In traditional eye-tracking FPC structures, the infrared LED chip is far from the eyeball, resulting in a low field of view, high cost, and large chip size, which affects vision.
By employing a transparent substrate and a grid-like copper wire layer design, the infrared LED bare chip is placed closer to the eyeball, reducing the number and size of chips, and the chip is protected by encapsulation through a transparent substrate.
It increases the field of view that eye movement can detect, reduces costs, does not affect vision, and reduces the size of the infrared LED bare chip.
Smart Images
Figure CN223694236U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of eye tracking, especially to an eye tracking FPC structure and frameless glasses. BACKGROUND
[0002] Eye tracking FPC is the key part of the overall scheme of eye tracking, infrared LED emits light to eyeball, and infrared camera can capture the light on eyeball, and eye tracking is carried out through corneal reflection center and pupil center (pupil corneal reflection method);
[0003] The traditional eye tracking FPC structure is as shown in the drawings, which is composed of a substrate, a metal circuit and an infrared LED chip, and the substrate is a non-transparent FPC substrate, as shown in the drawings, and the cross section of the traditional eye tracking FPC structure is as shown in the drawings, the infrared LED chip is connected with the metal circuit through solder paste, and SMT process is generally adopted, and the traditional LED packaging is composed of a lead frame and a second chip body, lead bonding is generally adopted for packaging, and the common size on the market is 1.0mm*0.5mm*0.4mm, however, the traditional eye tracking FPC structure has the following problems: the infrared LED chip is far away from the eyeball, the eye movement detectable field of view is low, the number of infrared LED chips used is large, the cost is high, and the volume of the infrared LED chip is large, which affects the viewing line of sight. Figure 5 Figure 6 Figure 7 The utility model discloses the following technical scheme: an eye tracking FPC structure, including the upper transparent substrate, and the lower transparent substrate, and a plurality of infrared LED bare chips are arranged between the upper transparent substrate and the lower transparent substrate;
[0004] In order to solve the above problems, the utility model aims at providing an eye tracking FPC structure and frameless glasses.
[0005] The utility model discloses the following technical scheme: an eye tracking FPC structure, including the upper transparent substrate, and the lower transparent substrate, and a plurality of infrared LED bare chips are arranged between the upper transparent substrate and the lower transparent substrate;
[0006] Among them, the upper transparent substrate includes the upper base layer of transparent and the upper metal layer of grid shape arranged on the upper base layer;
[0007] The lower transparent substrate includes the lower base layer of transparent and the lower metal layer of grid shape arranged on the lower base layer;
[0008] The infrared LED bare chip includes the first chip body, and the upper electrode layer and the lower electrode layer are arranged on the upper and lower sides of the first chip body respectively, the upper electrode layer is electrically connected with the upper metal layer of the upper transparent substrate, and the lower electrode layer is electrically connected with the lower metal layer of the lower transparent substrate.
[0009] Further, the upper metal layer in a grid shape and the lower metal layer in a grid shape are respectively an upper copper wire layer and a lower copper wire layer.
[0010] Further, the upper electrode layer arranged on the first chip body is a negative electrode layer, and the lower electrode layer arranged on the first chip body is a positive electrode layer.
[0011] Further, the copper wire width in the upper copper wire layer in a grid shape and the lower copper wire layer in a grid shape is less than 3 um, and the grid size is greater than 220 um.
[0012] Further, the size of the infrared LED bare chip is 50 um*50 um-190 um*190 um.
[0013] Further, the height of the infrared LED bare chip is 175 um.
[0014] A frameless glasses applied in an eye movement tracking system, the frameless glasses comprising a lens and the above-mentioned eye movement tracking FPC structure.
[0015] The beneficial effects of the utility model are: through the upper base layer of the upper transparent substrate and the lower base layer of the lower transparent substrate are transparent, the copper wire width in the upper copper wire layer and the lower copper wire layer is less than 3 um, and the grid size is greater than 220 um, so that the upper copper wire layer and the lower copper wire layer are not visible 2 cm away from the glasses, so that the infrared LED bare chip can be closer to the eyeball, and the line of sight is not affected, the eye movement detectable field of view is improved, in addition, the infrared LED bare chip can be closer to the eyeball, the number of LED used can be reduced, and the cost is reduced, further, through the size of the infrared LED bare chip being 50 um*50 um-190 um*190 um, the chip volume can be reduced, the line of sight is not affected, and through the packaging mode of the upper transparent substrate and the lower transparent substrate, the infrared LED bare chip is protected, and the volume of the usable infrared LED bare chip is further reduced. BRIEF DESCRIPTION OF DRAWINGS
[0016] Figure 1 It is a cross-sectional perspective view of the utility model.
[0017] Figure 2 It is a three-dimensional structure schematic view of the lower transparent substrate of the utility model.
[0018] Figure 3 It is a three-dimensional structure schematic view of the upper transparent substrate of the utility model.
[0019] Figure 4 It is a top view of the infrared LED bare chip of the utility model.
[0020] Figure 5A schematic diagram of a stereoscopic structure of an eye movement tracking FPC structure in the prior art.
[0021] Figure 6 A cross-sectional perspective view of an eye movement tracking FPC structure in the prior art.
[0022] Figure 7 A schematic diagram of a structure of an infrared LED chip.
[0023] Figure 8 A schematic diagram of a structure of a second embodiment of frameless glasses.
[0024] The marks in the drawings are: 1-upper transparent substrate, 11-upper base layer, 12-upper copper wire layer, 2-lower transparent substrate, 21-lower base layer, 22-lower copper wire layer, 3-infrared LED bare chip, 31-negative electrode layer, 32-first chip body, 33-positive electrode layer, 4-substrate, 5-infrared LED chip, 51-plastic sealing material, 52-effective light-emitting area, 53-lead frame, 54-second chip body, 55-gold wire, 6-metal circuit, 7-eyeball, 8-pitch, 9-solder paste, 10-lens. DETAILED DESCRIPTION
[0025] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The drawings show several embodiments of the present application. However, the present application can be realized in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.
[0026] It should be noted that when an element is referred to as being "fixedly attached" to another element, it can be directly on the other element or there can be intervening elements. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements can be present. As used herein the terms "vertical", "horizontal", "left", "right", and the like are merely for purposes of illustration.
[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.
[0028] As Figures 5-7As shown, it is an eye tracking FPC structure in the prior art, the eye tracking FPC structure in the prior art comprises a substrate 4, the substrate 4 is a non-transparent FPC substrate, a metal line 6 is arranged on the substrate 4, eight infrared LED chips 5 are arranged in a ring array on the metal line 6, the distance 8 between each infrared LED chip 5 and an eyeball 7 is the same, the metal line 6 is connected with the infrared LED chip 5 through tin paste 9, and generally, an SMT process is adopted;
[0029] The infrared LED chip 5 is 1.0mm*0.5mm*0.4mm in size; the infrared LED chip 5 comprises plastic sealing material 51, two lead frames 53 arranged in the plastic sealing material 51, a second chip body 54 arranged on one of the lead frames 53, the second chip body 54 is connected with the two lead frames 53 through two gold wires 55 respectively, and an effective light-emitting area 52 is arranged above the second chip body 54.
[0030] The metal line 6 in the eye tracking FPC structure in the prior art has a width of at least 0.5mm, is visible to the naked eye, and the eye tracking FPC structure in the prior art cannot be used to manufacture frameless glasses.
[0031] As shown in the drawings, Figures 1-4 As shown, it is a first embodiment of the utility model, the embodiment provides an eye tracking FPC structure, which comprises an upper transparent substrate 1, a lower transparent substrate 2 and a plurality of infrared LED bare chips 3 arranged between the upper transparent substrate 1 and the lower transparent substrate 2.
[0032] The upper transparent substrate 1 is composed of a copper grid electrode etched from copper+PET substrate, and the lower transparent substrate 2 is also composed of a copper grid electrode etched from copper+PET substrate; in the embodiment, five infrared LED bare chips 3 are arranged between the upper transparent substrate 1 and the lower transparent substrate 2, as shown in the drawings, Figure 2 and Figure 3 Two infrared LED bare chips 3 are located on the upper side of the upper transparent substrate 1 and the lower transparent substrate 2, and the two infrared LED bare chips 3 on the upper side are spaced apart but on the same straight line, two infrared LED bare chips 3 are located on the lower side of the upper transparent substrate 1 and the lower transparent substrate 2, and the two infrared LED bare chips 3 on the lower side are also spaced apart but on the same straight line, and one infrared LED bare chip 3 is located between the infrared LED bare chips 3 on the upper and lower sides.
[0033] Specifically, the upper transparent substrate 1 comprises a transparent upper base layer 11 and an upper metal layer in a grid shape arranged on the upper base layer 11; the lower transparent substrate 2 comprises a transparent lower base layer 21 and a lower metal layer in a grid shape arranged on the lower base layer 21; the upper metal layer in a grid shape and the lower metal layer in a grid shape are respectively an upper copper wire layer 12 and a lower copper wire layer 22; the copper wire width in the upper copper wire layer 12 in a grid shape and the lower copper wire layer 22 in a grid shape is less than 3um, and the grid size is greater than 220um, so that the upper copper wire layer 12 and the lower copper wire layer 22 2cm away from the glasses are visually invisible.
[0034] The infrared LED bare chip 3 comprises a first chip body 32, an upper electrode layer and a lower electrode layer arranged on the upper and lower sides of the first chip body 32 respectively; the upper electrode layer is electrically connected with the upper metal layer of the upper transparent substrate 1, and the lower electrode layer is electrically connected with the lower metal layer of the lower transparent substrate 2; the upper electrode layer arranged on the first chip body 32 is a negative electrode layer 31, and the lower electrode layer arranged on the first chip body 32 is a positive electrode layer 33; thus the upper transparent substrate 1 serves as a negative electrode, and the lower transparent substrate 2 serves as a positive electrode; the size of the infrared LED bare chip 3 is 50um*50um-190um*190um, and the height of the infrared LED bare chip 3 is 175um; the negative electrode layer 31 of the infrared LED bare chip 3 is first fixed on the upper copper wire layer 12 of the upper transparent substrate 1 by a die bonding machine to ensure a certain flatness, a PET line layer+glass composite layer is used, the flatness of the glass is generally <L*0.08%mm, the PET is a flexible material and is prone to warping after processing, and the flatness of the PET is generally L*1%mm, L being length, thus the flatness is ensured, and the lower copper wire layer 22 of the lower transparent substrate 2 is connected with the positive electrode layer 33 of the infrared LED bare chip 3 by a bonding method, thus the lower transparent substrate 2 is bonded with the upper transparent substrate 1, and in the bonding process, it is necessary to confirm that the lower copper wire layer 22 of the lower transparent substrate 2 is completely aligned with the positive electrode layer 33 of the infrared LED bare chip 3 to ensure that the bonding is conductive, and further to ensure a certain conductivity, low-temperature tin paste 9 can be printed on the lower copper wire layer 22 of the lower transparent substrate 2, and after bonding with the positive electrode layer 33 of the infrared LED bare chip 3, reflow soldering is performed to ensure the welding firmness.
[0035] In summary, by making the upper base layer 11 of the upper transparent substrate 1 and the lower base layer 21 of the lower transparent substrate 2 transparent, and by making the copper wire width in the upper copper wire layer 12 and the lower copper wire layer 22 less than 3 um and the grid size greater than 220 um, the copper wire layer 12 and the lower copper wire layer 22 are visually invisible at a distance of 2 cm from the glasses, so that the infrared LED bare chip 3 can be closer to the eyeball 7 without affecting the line of sight, improving the eye movement detectable field of view, and reducing the number of LEDs used and reducing the cost by making the infrared LED bare chip 3 closer to the eyeball 7. Further, by using the infrared LED bare chip 3 with a size of 50um*50um-190um*190um, the chip volume can be reduced without affecting the viewing line of sight, and the packaging method of the upper transparent substrate 1 and the lower transparent substrate 2 protects the infrared LED bare chip 3 while further reducing the volume of the infrared LED bare chip 3 that can be used.
[0036] As Figure 8 shown, the second embodiment of the utility model provides a frameless glasses applied in an eye movement tracking system, the frameless glasses include a lens 10 and the eye movement tracking FPC structure in the first embodiment, and the eye movement tracking FPC structure is arranged on the lens 10.
[0037] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.
[0038] The above-described embodiments only express several embodiments of the utility model, and the description is more specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the utility model, a number of modifications and improvements can be made, which are within the protection scope of the utility model. Therefore, the protection scope of the utility model patent should be subject to the appended claims.
Claims
1. An eye-tracking FPC structure, characterized by, The infrared LED bare chip is arranged between the upper transparent substrate and the lower transparent substrate. The upper transparent substrate comprises a transparent upper base layer and an upper metal layer in a grid shape arranged on the upper base layer. The lower transparent substrate comprises a transparent lower base layer and a lower metal layer in a grid shape arranged on the lower base layer. The infrared LED bare chip comprises a first chip body, an upper electrode layer and a lower electrode layer arranged on the upper and lower sides of the first chip body respectively; the upper electrode layer is electrically connected with the upper metal layer of the upper transparent substrate, and the lower electrode layer is electrically connected with the lower metal layer of the lower transparent substrate.
2. The eye-tracking FPC structure of claim 1, wherein, The upper metal layer in a grid shape and the lower metal layer in a grid shape are upper copper wire layers and lower copper wire layers respectively.
3. The eye-tracking FPC structure of claim 1, wherein, The upper electrode layer arranged on the first chip body is a negative electrode layer, and the lower electrode layer arranged on the first chip body is a positive electrode layer.
4. The eye-tracking FPC structure of claim 2, wherein, The copper wire width of the upper copper wire layer in a grid shape and the lower copper wire layer in a grid shape is less than 3 um, and the grid size is greater than 220 um.
5. The eye-tracking FPC structure of claim 1, wherein, The size of the infrared LED bare chip is 50 um*50 um-190 um*190 um.
6. The eye-tracking FPC structure of claim 1, wherein, The height of the infrared LED bare chip is 175 um.
7. A rimless eyeglass for use in an eye tracking system, the eyeglass comprising: The frameless glasses comprise a lens and the eye movement tracking FPC structure of any one of claims 1-6.