Assistant light source and front-light
AssigneeKoninklijke Philips Electronics N.V.
InventorAkimitsu Tsuda
Life of this patent
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Abstract
To provide an assistant light source and a front-light emitting light to the light guide plate efficiently. A sectional shape of prism 14a in the center of light stick is isosceles triangle having a tip angle (T°) of 100° and a tilt angle (a1) of 40°. The depth of the prism 14a is D1 μm. A sectional shape of prism 14b in a ¼ position from an end of light stick is triangle having a tip angle (T°) of 100° and a tilt angle (a2) of 34.8°. The depth of the prism 14b is D2 μm. A sectional shape of prism 14c in an end of light stick is triangle having a tip angle (T°) of 100° and a tilt angle (a3) of 24.05°. The depth of the prism 14c is D3 μm.
Claims14
An assistant light source comprising:
- an elongated light stick having a reflecting prism face with a plurality of prisms and having light emitting face opposed to said reflecting prism face, wherein an incident light is transmitted inside thereof, the transmitted light is reflected on said reflecting prism face, and the reflected light is emitted from said light emitting face;
- and
- light generating means arranged on both sides of said light stick for generating the light for emitting to said light stick;
- wherein said plurality of prisms has a sectional shape in consideration of path in direct light from said light generating means and path in light reflected on said light emitting face.
Dependencies are inferred from the claim text.