IP Library › Granted Patent US 12,601,858
Granted Patent B2
US 12,601,858 · App. 18/240,884 · Granted Apr 14, 2026

Light control film

Inventors: Yiren Xia (Milton Keynes, GB); Timothy Smeeton (Milton Keynes, GB)
Assignee: Envisics Ltd
G02B1/115B29D11/00634B29D11/00788B32B38/0004G02B1/12G02B27/0101B32B2307/40G02B2027/0118G02B2027/0194G02B2207/123
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Quick Facts
Patent No.
US 12,601,858
App. No.
18/240,884
Granted
Apr 14, 2026
Kind
B2
Abstract

A method of manufacturing a light control film. The method includes providing a plurality of alternating layers of transparent material and light absorbing material, where the alternating layers of transparent material and light absorbing material are stacked in a stacking direction. The method also includes cutting, with a triangle wave-shaped edge, across the plurality of alternating layers of transparent material and light absorbing material in a first cutting plane and a second cutting plane thereby resulting in the light control film including a serrated first surface and a serrated second surface, wherein each of the first and second cutting planes is orientated at an angle less than 90° to the stacking direction. The triangle wave-shaped edge includes a cutting edge with a triangular wave shape perpendicular to the first and/or second cutting plane.

Claims (27)

1 . A method of manufacturing a light control film, the method comprising:

providing a plurality of alternating layers of transparent material and light absorbing material, wherein the alternating layers of transparent material and light absorbing material are stacked in a stacking direction; and

cutting, with a triangle wave-shaped edge, across the plurality of alternating layers of transparent material and light absorbing material in a first cutting plane and a second cutting plane thereby resulting in the light control film comprising a serrated first surface and a serrated second surface, wherein each of the first and second cutting planes is orientated at an angle less than 90° to the stacking direction;

wherein the triangle wave-shaped edge comprises a cutting edge with a triangular wave shape perpendicular to the first and/or second cutting plane.

2 . The method of claim 1 , further comprising placing the light control film onto a rigid, optically transparent serrated substrate to support the light control film.

3 . The method of claim 1 , wherein the providing the plurality of alternating layers of transparent material and light absorbing material comprises:

providing a first layer of uncured transparent silicone rubber;

providing a first layer of uncured black silicone rubber onto the first layer of uncured transparent silicone rubber;

providing a second layer of uncured transparent silicone rubber onto the first layer of uncured black silicone rubber such that the first layer of uncured black silicone rubber is between the first and second layers of uncured transparent silicone rubber; and

providing a second layer of uncured black silicone rubber onto the second layer of uncured transparent silicone rubber such that the second layer of uncured transparent silicone rubber is between the first and second layers of uncured black silicone rubber.

4 . The method of claim 3 , wherein providing the plurality of alternating layers of transparent material and light absorbing material further comprises partially curing the layers of uncured silicone rubber to set a thickness of the layers.

5 . The method of claim 4 , wherein providing the plurality of alternating layers of transparent material and light absorbing material further comprises fully curing layers of uncured silicone rubber.

6 . The method of claim 3 , wherein providing the plurality of alternating layers of transparent material and light absorbing material further comprises fully curing layers of uncured silicone rubber.

7 . The method of claim 1 , wherein the triangle wave-shaped edge comprises ridges, and wherein cutting across the plurality of alternating layers comprises aligning the ridges of the triangle wave-shaped edge with edges of the layers of light absorbing material.

8 . The method of claim 7 , wherein the triangle wave-shaped edge comprises front facets and back facets that define the triangle wave-shape, wherein ridges are defined by where the front facets meet the back facets.

9 . The method of claim 8 , wherein cutting across the alternating layers comprises orientating the triangle wave-shaped edge such that angles between the back facets and the first and/or second cutting plane is substantially the same as angles between the layers of light absorbing material and the first and/or second cut plane.

10 . The method of claim 1 , wherein the serrated first surface comprises a first front facet at an angle greater than 35° to the first serrated surface.

11 . The method of claim 1 , wherein the serrated second surface comprises a second front facet at an angle greater than 35° to the second serrated surface.

12 . The method of claim 1 , wherein each of the layers of transparent material comprises opposing rough surfaces configured to scatter light.

13 . The method of claim 1 , wherein each layer of light absorbing material has a thickness of 10 μm to 100 μm.

14 . The method of claim 1 , wherein each layer of transparent material has a thickness of 0.1 mm to 10 mm.

15 . The method of claim 1 , further comprising applying an anti-reflective coating on the serrated first and/or second surface.

16 . The method of claim 1 , wherein each layer of the transparent material is wedge shaped.

17 . The method of claim 1 , wherein the layers of the plurality of alternating layers are parallel to each other.

18 . A method of manufacturing a head-up display for a vehicle, the method comprising:

providing an optical component having a reflective surface arranged, during head-up display operation, in a configuration that is conducive to sunlight glare; and

disposing a light control film manufactured using the method of claim 1 on the reflective surface of the optical component.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 5, 2026
From: ENVISICS LTD
To: DUALITAS LTD
Reel/Frame 076113/0595 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 18, 2023
From: XIA, YIREN; SMEETON, TIMOTHY
To: ENVISICS LTD
Reel/Frame 064941/0217 →
Priority Claims (1)
GB 2212909 · Sep 5, 2022 · national
Continuity (1)
Related Publication 20240077652A1 · Mar 7, 2024
References Cited (29)
US 4874671A · Tahara · 1989 [cited by examiner]
US 5909314A · Oka · 1999 [cited by examiner]
US 6542298B1 · Aoki · 2003 [cited by applicant]
US 6589649B2 · Oya · 2003 [cited by examiner]
US 12181668B2 · Smeeton · 2024 [cited by applicant]
US 20030137758A1 · Ikeda · 2003 [cited by applicant]
US 20040191548A1 · Takemoto · 2004 [cited by applicant]
US 20050200952A1 · Niwa · 2005 [cited by applicant]
US 20190346615A1 · Johnson · 2019 [cited by applicant]
US 20200026077A1 · Christmas · 2020 [cited by applicant]
US 20210072556A1 · Kim · 2021 [cited by examiner]
US 20210157136A1 · Nam · 2021 [cited by examiner]
US 20220357644A1 · Hirata · 2022 [cited by examiner]
US 20230314802A1 · Smeeton · 2023 [cited by applicant]
US 20230324683A1 · Timothy · 2023 [cited by applicant]
US 20240019694A1 · Döbler · 2024 [cited by applicant]
CN 109814327A · 2019 [cited by applicant]
DE 2914682A1 · 1981 [cited by applicant]
DE 102018213061A1 · 2020 [cited by applicant]
GB 2047912A · 1980 [cited by applicant]
GB 2607672A · 2022 [cited by applicant]
JP 2006100125A · 2006 [cited by applicant]
JP 2006119365A · 2006 [cited by applicant]
JP 2014063106A · 2014 [cited by applicant]
JP 2017167326A · 2017 [cited by applicant]
KR 20050034247A · 2005 [cited by applicant]
WO 2015186675A1 · 2015 [cited by applicant]
Copending U.S. Appl. No. 18/240,918, filed Aug. 31, 2023. [cited by applicant]
Search Report in United Kingdom, Patent Application No. GB2212909.2, dated Mar. 3, 2023. [cited by applicant]