Light guiding member and bifurcated linear light source apparatus

• US 20090003784A1
• Filed: 08/29/2008
• Published: 01/01/2009
• Est. Priority Date: 03/01/2007
• Status: Active Grant

• Current Assignee: Ushio Denki Kabushiki Kaisha
• Original Assignee: Ushio Denki Kabushiki Kaisha
• Inventors: Hata, Hiroshige, Kabuki, Kiyoyuki, Kamei, Koichi
• Granted Patent: US 7,953,312 B2
• Time in Patent Office: Days
• US Class Current: 385/119
• CPC Class Codes: B41J 2/45 using light-emitting diode [LED] or laser arrays
• CPC Class Codes: G02B 2006/0098 for scanning
• CPC Class Codes: G02B 6/001 the light being emitted along at least a portion of the lateral surface of the fibre
• CPC Class Codes: H04N 1/02815 Means for illuminating the original, not specific to a particular type of pick-up head
• CPC Class Codes: H04N 1/02835 in combination with a light guide, e.g. optical fibre, glass plate light-guides per se G02B6/00

Abstract

A light guiding member having a light direction changing face which extends in a longitudinal direction of the light guiding member and a light emitting face which faces the light guiding member, wherein the light direction changing face includes two faces arranged so that vertical faces which extend in the longitudinal direction and are respectively vertical to the two faces, intersect with each other. Also, a bifurcated linear light source apparatus comprises a LED, a light guiding member which is made up of a transparent rod shape member, and which emits light generated by the LED, in two directions, from a longitudinal direction side face of the transparent rod shape member, and a reflection mirror which reflects the light emitted in one of the two directions, to the other direction of the two directions.

Claims

1. A light guiding member having a light direction changing face which extends in a longitudinal direction of the light guiding member and a light emitting face which faces the light guiding member, wherein the light direction changing face includes two faces arranged so that vertical planes which extend in the longitudinal direction and are respectively vertical to the two faces, intersect with each other.

2. The light guiding member according to claim 1, wherein a relation of θ

1≧

θ

2 is satisfied, when an intersection angle formed by the vertical planes at an intersection thereof is represented as θ

1, and an angle which is formed by center-of-curvature lines which pass through respective two intersection points of the vertical faces and the light emitting face in a side of the light emitting face, is represented as θ

2.

3. The light guiding member according to claim 1, wherein the light direction changing face is in a concave shape, with respect to a short side direction of the light guiding member.

4. The light guiding member according to claim 2, wherein the light direction changing face is in a concave shape, with respect to a short side direction of the light guiding member.

7. A bifurcated linear light source apparatus comprising:

a light guiding member according to claim 1,

a light source provided so as to face an optical incidence section which is provided at least in one of both ends of the light guiding member in the longitudinal direction, and

a reflection mirror which reflects light emitted from the light emitting face in one of the two directions, to the other direction of the two directions, in which a length of the reflection mirror is the same as that of the light emitting face of the light guiding member, and the reflection mirror is provided in a position approximately symmetrical to the light emitting face with respect to a face vertical to a center of a document reading face.

8. A bifurcated linear light source apparatus comprising:

a light guiding member according to claim 2,

a light source provided so as to face an optical incidence section which is provided at least in one of both ends of the light guiding member in the longitudinal direction, and

a reflection mirror which reflects light emitted from the light emitting face in one of the two directions, to the other direction of the two directions, in which a length of the reflection mirror is the same as that of the light emitting face of the light guiding member, and the reflection mirror is provided in a position approximately symmetrical to the light emitting face with respect to a face vertical to a center of a document reading face.

9. A bifurcated linear light source apparatus comprising:

a light guiding member according to claim 3,

a light source provided so as to face an optical incidence section which is provided at least in one of both ends of the light guiding member in the longitudinal direction, and

a reflection mirror which reflects light emitted from the light emitting face in one of the two directions, to the other direction of the two directions, in which a length of the reflection mirror is the same as that of the light emitting face of the light guiding member, and the reflection mirror is provided in a position approximately symmetrical to the light emitting face with respect to a face vertical to a center of a document reading face.

10. A bifurcated linear light source apparatus comprising:

a light guiding member according to claim 4,

a light source provided so as to face an optical incidence section which is provided at least in one of both ends of the light guiding member in the longitudinal direction, and

a reflection mirror which reflects light emitted from the light emitting face in one of the two directions, to the other direction of the two directions, in which a length of the reflection mirror is the same as that of the light emitting face of the light guiding member, and the reflection mirror is provided in a position approximately symmetrical to the light emitting face with respect to a face vertical to a center of a document reading face.

5. A light guiding member in a rod shape, which has a light direction changing face which extends in a longitudinal direction of the light guiding member and a light emitting face which faces the light guiding member, wherein the light emitting face of the light guiding member is formed of two curved surfaces in which respective curvatures thereof are equal to or different from each other.

11. A bifurcated linear light source apparatus comprising:

a light guiding member according to claim 5,

a light source provided so as to face an optical incidence section which is provided at least in one of both ends of the light guiding member in the longitudinal direction, and

a reflection mirror which reflects light emitted from the light emitting face in one of the two directions, to the other direction of the two directions, in which a length of the reflection mirror is the same as that of the light emitting face of the light guiding member, and the reflection mirror is provided in a position approximately symmetrical to the light emitting face with respect to a face vertical to a center of a document reading face.

6. A bifurcated linear light source apparatus comprising:

a LED;

a light guiding member which is made up of a transparent rod shape member, and which emits light generated by the LED, in two directions, from a longitudinal direction side face of the transparent rod shape member, and

a reflection mirror which reflects the light emitted in one of the two directions, to the other direction of the two directions.