IP Library › Granted Patent US 12,730,358
Granted Patent B2
US 12,730,358 · App. 18/579,638 · Granted Sep 8, 2026

Lens hood

Inventor: Naoki Sakazume (Tokyo, JP)
Assignee: SOMAR CORPORATION
G03B11/045G02B1/111
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Quick Facts
Patent No.
US 12,730,358
App. No.
18/579,638
Granted
Sep 8, 2026
Kind
B2
Abstract

A lens hood has an antireflection film for shielding an unnecessary light entering a photographic lens of a camera. Here, (A) indicates a resin component, (B) unevenness forming particles, (B1) inorganic-type small particles having a particle diameter (d1) of 0.05 μm to 0.4 μm, (B2) inorganic-type large particles having a particle diameter (d2) of 2 μm to 6 μm, and (C) a diluent solvent. The antireflection film is a membrane formed from a liquid composition via spray coating and has a thickness of 2 to 40 μm. The liquid composition has at least (A), (B) and (C). The (B) is contained in an amount of 20% by mass to 60% by mass in 100% by mass of a total amount of the total solid content in the composition. The (B) contains (B1) and (B2) in an amount of 90% by mass or more. A mass ratio of (B2) to (B1):1 is 1.8 to 3.3.

Claims (31)

1 . A lens hood attached to a photographic lens on a side of a photography subject for shielding an unnecessary light entering to the photographic lens: wherein

an inner wall surface of a hood body has an antireflection film;

the antireflection film is configured by a membrane composed of a laminate of a solid particle formed from a liquid composition and having a thickness of 2 μm or more and 40 μm or less;

the solid particle comprises at least (A) and (B), wherein

(B) is contained in an amount of 20% by mass or more and 60% by mass or less in a total amount of 100% by mass of the solid particle;

(B) comprises (B1) having a particle diameter (d 1 ) of 0.05 μm or more and 0.4 μm or less and (B2) having a particle diameter (d 2 ) of 2 μm or more and 6 μm or less in an amount of 90% by mass or more, and a mass ratio of (B2) with respect to (B1):1 is 1.8 or more and 3.3 or less;

(A) is a resin component;

(B) is unevenness forming particles;

(B1) is inorganic-type small particles; and

(B2) is inorganic-type large particles.

2 . The lens hood according to claim 1 , wherein (B1) comprises carbon black.

3 . The lens hood according to claim 2 , wherein, on an outermost surface of a surface formed with a membrane, glossiness against an incident light with an incident angle of 60° is less than 1%, glossiness against an incident light with an incident angle of 85° is less than 5%, reflectance against a light having a wavelength of 550 nm is 4% or less, an L value in CIELAB color space system by SCE method of 22 or less, and an optical density is 1.0 or more.

4 . The lens hood according to claim 3 , on an outermost surface of a surface formed with a membrane, a maximum height Rz based on JIS B0601: 2001 is 7 μm or more, an average length Rsm of contour curve elements is 80 μm or more, a skewness Rsk of a contour curve is 0.3 or less, and Kurtosis of a contour curve Rku is 3 or more.

5 . The lens hood according to claim 1 , wherein, on an outermost surface of a surface formed with a membrane, glossiness against an incident light with an incident angle of 60° is less than 1%, glossiness against an incident light with an incident angle of 85° is less than 5%, reflectance against a light having a wavelength of 550 nm is 4% or less, an L value in CIELAB color space system by SCE method of 22 or less, and an optical density is 1.0 or more.

6 . The lens hood according to claim 5 , on an outermost surface of a surface formed with a membrane, a maximum height Rz based on JIS B0601: 2001 is 7 μm or more, an average length Rsm of contour curve elements is 80 μm or more, a skewness Rsk of a contour curve is 0.3 or less, and Kurtosis of a contour curve Rku is 3 or more.

7 . The lens hood according to claim 1 , wherein (B2) comprises at least one selected from a group consisting of a composite silica obtained by synthesizing carbon black and silica at a nano level, a conductive silica and a black silica.

8 . The lens hood according to claim 7 , wherein (B1) comprises carbon black.

9 . The lens hood according to claim 7 , wherein the particle diameter (d 2 ) of (B2) is 10 times or more and 40 times or less the particle diameter (d1) of (B1).

10 . The lens hood according to claim 7 , wherein (B) contains unevenness forming particles other than (B1) and (B2), a particle diameter (dmax) of the unevenness forming particles having the maximum particle diameter is 10 times or more and 40 times or less a particle diameter (dmin) of the unevenness forming particles having the minimum particle diameter.

11 . The lens hood according to claim 7 , wherein (A) comprises an acrylic resin.

12 . The lens hood according to claim 1 , wherein the particle diameter (d 2 ) of (B2) is 10 times or more and 40 times or less the particle diameter (d 1 ) of (B1).

13 . The lens hood according to claim 1 , wherein (B) contains unevenness forming particles other than (B1) and (B2), a particle diameter (dmax) of the unevenness forming particles having the maximum particle diameter is 10 times or more and 40 times or less a particle diameter (dmin) of the unevenness forming particles having the minimum particle diameter.

14 . The lens hood according to claim 1 , wherein (A) comprises an acrylic resin.

15 . An antireflection film to be formed on an inner wall surface of a lens hood, configured by a membrane composed of a laminate of a solid particle formed from a liquid composition and having a thickness of 2 μm or more and 40 μm or less: wherein

the solid particle comprises at least (A) and (B), wherein

(B) is contained in an amount of 20% by mass or more and 60% by mass or less in a total amount of 100% by mass of the solid particle;

(B) comprises (B1) having a particle diameter (d 1 ) of 0.05 μm or more and 0.4 μm or less and (B2) having a particle diameter (d 2 ) of 2 μm or more and 6 μm or less in an amount of 90% by mass or more, and a mass ratio of (B2) with respect to (B1): 1 is 1.8 or more and 3.3 or less;

(A) is a resin component;

(B) is unevenness forming particles;

(B1) is inorganic-type small particles; and

(B2) is inorganic-type large particles.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 16, 2024
From: SAKAZUME, NAOKI
To: SOMAR CORPORATION
Reel/Frame 066135/0969 →
Priority Claims (1)
JP 2021-120361 · Jul 21, 2021 · national
Continuity (1)
Related Publication 20240337902A1 · Oct 10, 2024
References Cited (26)
US 5909314A · Oka · 1999 [cited by examiner]
US 6116330A · Salyer · 2000 [cited by applicant]
US 10254628B2 · Ono · 2019 [cited by applicant]
US 20120251095A1 · Ono et al. · 2012 [cited by applicant]
US 20160131961A1 · Ito · 2016 [cited by applicant]
US 20170146888A1 · Ono · 2017 [cited by applicant]
US 20230046475A1 · Sakamura et al. · 2023 [cited by applicant]
EP 4082891A1 · 2022 [cited by examiner]
JP 2003105235A · 2003 [cited by applicant]
JP 2012194514A · 2012 [cited by applicant]
JP 2013054393A · 2013 [cited by applicant]
JP 201651012A · 2016 [cited by applicant]
JP 2016090950A · 2016 [cited by applicant]
JP 201852804A · 2018 [cited by applicant]
JP 2018144852A · 2018 [cited by applicant]
JP 2019200392A · 2019 [cited by applicant]
JP 2020097730A · 2020 [cited by applicant]
WO 2011062055A1 · 2011 [cited by applicant]
WO 2021132585A1 · 2021 [cited by applicant]
JP 2020097730; Inoguchi et al. Surface Antireflection Coating for Atomization Coating, and Surface Antireflection Coated Film (Year: 2020). [cited by examiner]
Sakamura et al. (WO 2021132585) Black Light Shielding Member (Year: 2021). [cited by examiner]
Tanaka Naohiro, JP 2018144852, Adhesion Prevention Member, Container, and Manufacturing Method of Adhesion Prevention Member (Year: 2018). [cited by examiner]
CN 113574420 Fumiaki et al. Laminated Body for Anti-reflection Film, Anti-reflection Film and Manufacturing Method (Year: 2020). [cited by examiner]
WO 9845734 Tomokazu et al. Antireflection Films and Image Display Device (Year: 1998). [cited by examiner]
International Search Report Corresponding to International Application No. PCT/JP2022/027840 dated Oct. 11, 2022, 3 pages. [cited by applicant]
Japanese Office Action Corresponding to JP Application No. 2021-120361, dated Jun. 24, 2025, 10 pages. [cited by applicant]