Photoelectric sensor and method for controlling amplification of received light intensity in photoelectric sensor

摘要

A photoelectric sensor amplifies a received light intensity signal generated through light projection processing and light receiving processing, and performs detection processing using the amplified received light intensity signal. The photoelectric sensor is provided with a variable resistor that generates an adjustment command signal that changes linearly with respect to sensitivity adjustment manipulations performed by a user. Further, the sensor is provided with an amplifier including a variable gain amplifier configured such that the aforementioned adjustment command signal is inputted thereto. Further, the variable gain amplifier is adapted to convert the signal into a gain control signal that changes exponentially with respect to sensitivity adjustment manipulations and, further, is adapted to perform amplification processing using a gain according to the gain control signal.

主权项

1. A photoelectric sensor comprising:
an amplifier that amplifies a received light intensity signal generated through light projection processing and light receiving processing; a detector that performs detection processing using the amplified received light intensity signal; a variable resistor having a pair of fixed terminals and a movable terminal configured to move between the fixed terminals, according to a sensitivity adjustment manipulation performed by a user, wherein the amplifier includes:
a gain controller that receives an adjustment command signal that changes linearly with respect to the sensitivity adjustment manipulation performed by the user, and converts the adjustment command signal into a gain control signal that changes exponentially with respect to the sensitivity adjustment manipulation; anda variable amplifier that performs amplification processing using a gain according to the gain control signal, wherein a reference voltage is applied between the fixed terminals of the variable resistor, and a signal formed from a voltage drop resulting from a voltage division based on the position of the movable terminal between the fixed terminals is inputted, as the adjustment command signal, to the gain controller.