battery charge indicator

الوصف

Magic eye assembly, the red, green beads are submerged in liquids, the red beads density less than 1, whether battery for electric, red beads are floating up, in the magic eye on display is the middle of the point is red.

Charging process when solution density 1.**7, (namely achieve green beads own density value), the green beads began to rise, through the reflection principle, in the magic eye on display is green (ring), and in the middle is still red.

After discharge with solution density decreased, and the green beads with subsidence, the electric eye displays only in the middle of the red. The edge are white

After many charge and discharge, battery level drops, lower than the length of the electric eye, the red beads with subsidence, the electric eye shows the red ?