Light control film

• US 9,063,284 B2
• Filed: 06/16/2010
• Issued: 06/23/2015
• Est. Priority Date: 06/18/2009
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Jones, Vivian W., Theiss, Silva K., Gardiner, Mark E., Lauters, Michael E., Gaides, Gary E.
• Primary Examiner(s): Phan, James
• Application Number:
  US13/378,221
• Publication Number:
  US 20120154885A1
• Time in Patent Office: 1,833 Days
• Field of Search: 359/452, 359/454, 359/613, 359/614, 359/885, 359/227, 359/858
• US Class Current: 1/1
• CPC Class Codes: G02B 2207/123 Optical louvre elements, e.g. for directional light blocking
• CPC Class Codes: G02B 27/0994 Fibers, light pipes optical fibers per se G02B6/02
• CPC Class Codes: G02B 27/30 Collimators
• CPC Class Codes: G02B 5/22 Absorbing filters G02B5/201 - G02B5/208 take precedence
• CPC Class Codes: G02B 5/223 containing organic substances, e.g. dyes, inks or pigments

Abstract

Light control films, and a method for manufacturing tools used to microreplicate light control films.

Claims

1. A light control film, comprising:

a light input surface and a light output surface opposite the light input surface; and

alternating transmissive and non-transmissive regions disposed between the light input surface and the light output surface, each transmissive region having a width, W′

, at its narrowest region;

wherein the average pitch of successive transmissive regions, P, is 0.040 mm or less; and

wherein W′

/P>

0.75; and

wherein light incident on the light input surface exits the light output surface having a maximum relative brightness ratio (RBR) in the major viewing axis direction of 65 or greater and an effective polar viewing angle (EPVA) of 45°

or less.

2. The light control film of claim 1, wherein W′

/P>

0.80.

3. The light control film of claim 1, wherein light incident on the light input surface exits the light output surface having an effective polar viewing angle (EPVA) of 35°

or less.

4. The light control film of claim 1, wherein each transmissive region has an index of refraction N1, and each non-transmissive region has an index of refraction N2, where −

0.005<

N1−

N2<

0.

5. The light control film of claim 1 wherein each non-transmissive region comprises an optically absorptive material selected from a pigment, a dye, or a combination thereof.

6. The light control film of claim 1, wherein W′

is 0.030 mm or less.

7. The light control film of claim 1, wherein the transmissive region further comprises a width at its widest region, W, wherein W−

W′

is less than 5 μ

m.

8. A light control film, comprising:

a light input surface and a light output surface opposite the light input surface; and

alternating transmissive and non-transmissive regions disposed between the light input surface and the light output surface;

wherein the average pitch of successive transmissive regions is 0.040 mm or less; and

wherein light incident on the light input surface exits the light output surface having a maximum relative brightness ratio (RBR) in the major viewing axis direction of 65 or greater and an effective polar viewing angle (EPVA) of 45°

or less.

9. The light control film of claim 8, wherein the distance from the light input surface to the light output surface is less than 0.080 mm.