Light sensing illumination device for bicycle

A light sensing illumination device for bicycle, comprising:

• a seat, including a housing space and disposed on a bicycle;
• a reflector disposed in the housing space, the reflector including a reflection curved face and reflection plates, wherein the reflection curved face is in a continuous smooth arc shape facing an opening of the housing space, the reflection plates having a continuously arranged wave shape extending from the reflection curved face toward the opening of the housing space, the reflection curved face including a plurality of reflection areas connecting together without height and thickness difference between each two neighboring reflection areas, and the reflection areas including a first reflection area, a second reflection area, a third reflection area, and a fourth reflection area sequentially arranged along a longitudinal cross-sectional direction from a top portion to a bottom portion of the reflection curved face;
• and
• an illumination unit disposed in the housing space and projecting light beam toward the reflection curved face;
• wherein the light beam is projected to the reflection areas, the first reflection area provides a first reflection route for reflecting the light beam, the second reflection area provides a second reflection route for reflecting the light beam;
• wherein a first angle is between the first reflection route and a horizontal line, a second angle is between the second reflection route and the horizontal line, a ratio between the first angle and the second angle is 9:1;
• and
• wherein each of the third reflection area and the fourth reflection area generate a horizontal reflection route respectively, and all the reflection routes project the light beam toward a light condensed area.