A
Ambient Illuminance: The ambient operating illumination is expressed in terms of the Receiver surface illuminance and is defined as the illuminance when there is a ±20% change with respect to the value at a light reception output of 200 lx. This is not sufficient to cause malfunction at the operating illuminance limit.

B
Built-in Amplifier: Everything except the power supply is integrated in these Sensors. Through-beam Sensors are, however, divided into the Emitter comprised solely of the Emitter and the Receiver comprised of the Receiver, Amplifier,and Controller. The power supply is a standalone unit.

D
Dead Zone: The dead zone outside of the emission and reception areas near the lens surface in Mark Sensors, Distance-settable Sensors, Limited-reflective Sensors, Diffuse-reflective Sensors, and Retro-reflective Sensors. Detection is not possible in this area.

Different Frequency: The frequency of a sensor model that is different from the frequency of the standard models. A model with a different frequency causes less mutual interference. Using a standard model and a model with a different frequency enables close mounting.

Differential Coil Type: A type of Sensor that detects only the magnetic fields from eddy currents caused when metal approaches are detected. This type of Sensor has an excitation coil with a high-frequency oscillation and a couple of detector coils with a linked differential.

Differential Time: The reference time used to determine changes in the light reception signal when detecting objects using differential operation (i.e., detecting only rapid changes in the incident level). An object is detected if the change in the incident level exceeds the specified threshold value within the differential time.

Directional Angle: The angle where operation as a Photoelectric Sensor is possible for a Through-beam Sensor or Retro-reflective Sensor.

E
Excess Gain Studio: The ratio of the incident light to the threshold, expressed as follows: Incident light/Threshold x 100 (%). The margin shows whether the operation of the sensor is stable. It is also simply called "margin".

External Diagnosis Input Function: A function that stop light emission at any time by giving a signal to the external diagnosis input of a photoelectric sensor. For example with the Through-beam type, the emitter is turned ON and OFF when there is no sensing object between the emitter and receiver. If the receiver does not turn ON and OFF accordingly, there is an error in the sensor. This function thus allows sensor operation to be checked before system operation is started.

G
Gauge Pressure: The amount of pressure is expressed in terms of atmospheric pressure. It is referred to as "positive pressure" when it is greater than atmospheric pressure, and "negative pressure" when it is less than atmospheric pressure.

L
Leakage Current Characteristic: A characteristic that occurs because Two-wire Proximity Sensors are electrically configured with transistors and other components. This indicates the leakage current characteristics of the transistor in the output section. Generally speaking, the higher the voltage, the larger the leakage current.

Linearity: The analog output changes in an approximately linear fashion with respect to the detected pressure. The change, however, deviates slightly from an ideal straight line. This deviation is expressed as a percentage of the full scale.

Liquid Leakage Sensors: A sensor that detects leakage from facilities or machines, including various type of products, such as Sensing Bands, Point Sensors, Chemical-resistance Sensors, and Sensors resistant to high temperatures. Liquid Leakage Sensors are widely used in semiconductor production equipment and clean rooms.

M
Margin: The ratio of the incident light to the threshold, expressed as follows: Incident light/Threshold x 100 (%). The margin shows whether the operation of the sensor is stable. This term is formally called "excess gain ratio".

N
Non-Modulated Light: Non-modulated light refers to an uninterrupted beam of light at a specific intensity that is used with certain types of Sensors, such as Mark Sensors. Although these Sensors have fast response times, their drawbacks include short sensing distances and susceptibility to external light interference.

O
Optical Fiber Sensor: The Emitter and Receiver are connected by optical fiber.

Optically Synchronized: An optical communications method between Amplifier Units used to offset detection timing to prevent mutual interference for Fiber Sensors or Sensors with Separate Amplifier.

P
Perpendicular Sensing Distance: Expressed as the measured distance from the reference surface when the standard sensing object approaches from the radial direction (perpendicular to the sensing surface).

Photoelectric Sensors: Photoelectric Sensors detect objects, changes in surface conditions, and other items through a variety of optical properties.

Potentiometer: A resistor used to adjust the sensitivity of a proximity sensor. The sensing distance increases when the potentiometer is turned clockwise and decreases when it is turned counterclockwise.

Pressure Detection Range: The range of pressure that can be detected by the Sensor.

Pressure Sensors: A pressure sensor is a device equipped with a pressure-sensitive element that measures the pressure of a gas or a liquid against a diaphragm made of stainless steel, silicon, etc., and converts the measured value into an electrical signal as an output.

Proximity Sensors: Proximity Sensor includes all sensors that perform non-contact detection in comparison to sensors, such as limit switches, that detect objects by physically contacting them.

R
Residual Voltage Characteristic: A characteristic, like the leakage current characteristic, that occurs because the Sensor is electrically configured with a switch. For example, for a normally open model, the voltage would be 0 V when the sensor is ON but if the sensor is OFF, the voltage would not be the same as the power supply voltage. As a result, part of the voltage would remain in the switch due to the electrical characteristic of a transistor.

S
Self-Diagnosis Function: The self-diagnosis function checks for margin with respect to environmental changes after installation, especially ambient temperature, and informs the operator of the result through indicators and outputs. This function is an effective means of early detection of product failure, optical axis displacement, and accumulation of dirt on the lens over time.

Self-Powered: The Power Supply, Emitter, and Receiver are all installed in the same housing with these Sensors.

Semiconductor Distortion Gauge: A distortion gauge that operates using the following principle. The kinetic potential of the electrons in a semiconductor changes when the crystal structure of the semiconductor is distorted. This changes the carrier mobility in the semiconductor, resulting in a change in the electrical resistance. In a pressure sensor, external pressure distorts a diaphragm, causing distortion in the resistor section in the gauge. A voltage thus is output that is proportional to the pressure.

Sensing Distance: The distance from the reference position (reference surface) to the measured operation (reset) position when the standard sensing object is moved by the specified method.

Sensitivity Adjuster: An adjuster used to set the sensitivity of light reception.

Setting Distance: The distance from the reference surface to the (standard) sensing object transit position that allows stable use, including the effects of temperature and voltage.

Shielded: With a Shielded Sensor, magnetic flux is concentrated in front of the Sensor and the sides of the Sensor coil are covered with metal. The Sensor can be mounted by embedding it into metal.

Stability Indicator: An indicator that shows the amount of leeway in detection with respect to environmental changes, such as in the temperature, voltage, and dust, after installation.

Standard Mode: An operating mode of a Fiber Amplifier Unit. There are also a Long-distance Mode and a High-speed Mode.

Standard Sensing Object: The standard sensing object for both Through-beam Sensors and Retro-reflective Sensors is an opaque rod with a diameter larger than the length of a diagonal line of the optical system. In general, the diameter of the standard sensing object is the length of the diagonal line of the Emitter/Receiver lens for Through-beam Sensors, and the length of a diagonal line of the Reflector for Retro-reflective Sensors. For Diffuse-reflective Sensors, the standard sensing object is a sheet of whitepaper larger than the diameter of the emitted beam.

Super High Speed Mode: One of the modes of a Fiber Amplifier Unit, this mode provides the fastest response time. The sensing distance is the shortest.

Switching Capacity: The maximum size of load that can be switched by the output of a proximity sensor.

T
Teaching: Making the Sensor set the sensitivity, thresholds, etc.

Triangulation: A measurement method in which the target object is placed at one apex of a triangle and the length of the opposing side and angles to the target object are used to calculate the distance to the target object.

U
Unshielded: With an Unshielded Sensor, magnetic flux is spread widely in front of the Sensor and the sides of the Sensor coil are not covered with metal. This model is easily affected by surrounding metal objects (magnetic objects), so care must be taken in selecting the mounting location.

W
Withstand Pressure: The pressure that must be withstood without degraded performance after returning to the pressure detection range.