DUAL FILM LIGHT GUIDE FOR ILLUMINATING DISPLAYS

• US 20100309687A1
• Filed: 06/07/2010
• Published: 12/09/2010
• Est. Priority Date: 04/30/2007
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Gruhlke, Russell W., Xu, Gang, Bita, Ion, Sampsell, Jeffrey B., Mienko, Mark
• Granted Patent: US 8,373,821 B2
• Time in Patent Office: Days
• US Class Current: 362/627
• CPC Class Codes: G02B 26/001 based on interference in an adjustable optical cavity interference filters G02B5/28; devices or arrangements using multiple reflections in spectrometry or monochromators G01J3/26
• CPC Class Codes: G02B 6/0038 Linear indentations or grooves, e.g. arc-shaped grooves or meandering grooves, extending over the full length or width of the light guide
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer

Abstract

A front light guide panel including a plurality of embedded surface features is provided. The front light panel is configured to deliver uniform illumination from an artificial light source disposed at one side of the font light panel to an array of display elements located behind the front light guide while allowing for the option of illumination from ambient lighting transmitted through the light guide panel. The surface embedded surface relief features create air pockets within the light guide panel. Light incident on the side surface of the light guide propagates though the light guide until it strikes an air/light material guide interface at one on the air pockets. The light is then turned by total internal reflection through a large angle such that it exits an output face disposed in front of the array of display elements.

Claims

1-92. -92. (canceled)

93. A light guide system comprising:

a cover layer; and

a light guide body comprising a plurality of surface relief features extending into the light guide body;

wherein the cover layer and light guide body are configured to guide light therein, and wherein the cover layer is disposed adjacent to one or more of the surface relief features such that the cover layer and the one or more surface relief features of the light guide body form one or more cavities between the cover layer and the light guide body,

wherein the light guide body is thicker than the cover layer.

94. The light guide system of claim 93, wherein the light guide body comprises first and second layers bonded together.

95. The light guide system of claim 94, wherein the first and second layers of the light guide body comprise at least one of acrylic or polycarbonate.

96. The light guide system of claim 93, wherein the cover layer and light guide body have the same index of refraction.

97. The light guide system of claim 93, wherein the cavities are configured to totally internally reflect the light such that the light is no longer guided within the cover layer or light guide body.

98. The light guide system of claim 93, wherein the cavities comprise air pockets.

99. The light guide system of claim 93, wherein the cavities are filled with a filler material.

100. The light guide system of claim 99, wherein the filler material is reflective.

101. The light guide system of claim 93, wherein the cover layer is disposed over an array of display elements, the cover layer being closer to the display elements than the light guide body.

102. The light guide system of claim 93, wherein the one or more surface relief features comprise elongate microprisms.

103. The light guide system of claim 102, wherein the microprisms comprise adjacent sides that are multifaceted.

104. The light guide system of claim 93, wherein the one or more surface relief features comprise at least two adjacent facets angled with respect to one another.

105. The light guide system of claim 104, wherein the at least two adjacent facets have different angles of inclination with respect to one another.

106. The light guide system of claim 104, wherein the at least two adjacent facets comprise curved surfaces.

107. The light guide system of claim 93, wherein the one or more surface relief features comprises two vertical facets.

108. The light guide system of claim 93, wherein the one or more surface relief features have a reflective coating thereon.

109. The light guide system of claim 93, wherein the light guide body includes an edge through which light can be injected, the injected light being scattered out of the light guide body at the cavities.

110. The light guide system of claim 109, wherein the one or more surface relief features comprise at least two adjacent facets angled with respect to one another such that light injected through the edges is refracted at the cavities.

111. The light guide system of claim 109, wherein the one or more surface relief features comprise at least two adjacent facets angled with respect to one another such that light injected through the edges is turned via total internal reflection at the cavities.

112. The light guide system of claim 93, the cover layer further comprising:

a viewing face positioned opposite the planar surface.

113. The light guide system of claim 112, wherein the viewing face is planar.

114. A light guide system comprising:

means for guiding light comprising a plurality of means for redirecting light;

means for covering the light redirecting means;

means for displaying images, the displaying images means disposed under the light guiding means,

wherein the covering means and light guiding means are configured to guide light therein, and wherein the covering means is disposed adjacent to one or more of the plurality of light redirection means such that the covering means and the one or more light redirection means form one or more cavities between the covering means and the light guiding means, and wherein the light guiding means is thicker than the covering means.

115. The light guide system of claim 114, wherein the covering means is disposed over the displaying images means, the covering means being closer to the displaying images means than the light guiding means.

116. The light guide system of claim 114, wherein the covering means comprises a cover layer, the light guiding means comprises a light guide body, the displaying images means comprises a plurality of display elements, and the light redirecting means comprises surface relief features.

117. The light guide system of claim 116, wherein the plurality of display elements comprise interferometric modulators.