| 摘要 |
PROBLEM TO BE SOLVED: To control light emission power efficiently. SOLUTION: The communication equipment has a control means 50 that controls light emission power to sent in response to a level of received power and a light emission means 21 that is controlled by the means 50. The light emission means 27 has n-sets of drive means 30 that drive a light emitting element 32, and number of the light emitting elements 32 provided to an i-th (0<=i<=n-1) drive means is selected to be 2<i> . The light emission power over 2<n> stages is selected depending on the light receiving power. Thus, the light emission power is controlled in detail with a highest efficiency by a small number of light emitting elements and a small number of drive circuits. |
