Light propagation loss of the micron size optical waveguides is found to be improved from 1.8 to 0.6 dB/cm by capping waveguides by Al film. Al micromirrors for changing the light propagation direction in the vertical and horizontal planes were fabricated. Various shapes of Al corner mirrors to change the light direction in the horizontal plane were investigated. The straight simple mirror at an angle of 45° against the incident light has the largest reflectivity of 50%. Branched waveguides were also fabricated by using Al corner mirrors and resulted in the almost equal distribution of the light for three branches. Light emitting diodes (LEDs), micromirrors, waveguides and photodetectors have been integrated on a single chip and the signal transfer from the LED to the photodetector has been verified.