(Input-Output) Provides communication channels to system and to manufacturing process.

Abbreviation for International Electrotechnical Commission. This organization, headquartered in Geneva, Switzerland, writes and distributes recommended safety and performance standards for electrical products and components.

Institute of Electrical and Electronics Engineers. A membership organization involved in setting standards for computers and communications.

(Vision Sensing) Projection of an object or a scene onto an imager chip.

(Vision Sensing) The capture and generation of an image of an object or scene on the imager chip. Involves the use of illumination, optics, filters and the vision sensor.

The degree to which an image shows contrast.

(Vision Sensing) The physical device that replaces film in a digital camera system. Two common types are CCD and CMOS. Also known as imager or image sensor.

The opposition in an electric circuit to the flow of electrical current at a given frequency. Impedance consists of resistance, inductive reactance, and capacitive reactance. It is measured in Ohms.

Thermal generation of light, usually through radiant filaments in a bulb.

The light falling directly on an object.

The ratio of the velocity of light in a vacuum to the velocity of light in a specific material. Using 1.0 as the base reference, the higher the number, the slower light travels.

A fiber optic assembly having one control end and one sensing end. Used for piping photoelectric light from an emitter to the sensing location or from the sensing end to the receiver. Usually used in pairs in the opposed sensing mode, but can also be used side-by-side in the diffuse proximity mode or angled for the specular reflection or mechanical convergent mode.

The property of an electric circuit whereby an electromotive force (emf) is induced in it by a change of current in itself or in a neighboring circuit. When a current changing at the rate of one ampere per second induces a voltage of 1 volt, the inductance of the circuit is 1 henry.

A load that is predominantly inductive, so that the alternating load current lags behind the alternating voltage of the load.

Sensors with an oscillator and coil which radiate an electromagnetic field that induces eddy currents on the surface of metallic objects approaching the sensor face. The eddy currents dampen the oscillator energy. This energy loss is sensed as a voltage drop, which causes a change in the sensor's output state.

Light, with wavelengths greater than 800 nanometers (8000 Angstroms), that is invisible to the human eye. Infrared LEDs in emitters offer the highest amount of excess gain.

1. The signal (voltage or current) applied to a circuit to cause the output of that circuit to change state. 2. The terminals, jacks, or receptacle provided for reception of the input signal.

Condition initiated by the user to control a sensor's output(s) during sensing events. This condition may use one or two parameters or "points" within which is an acceptable range for sensing events to occur. 

The power source required by an electric or electronic device (e.g. a self-contained sensor) in order for the device to operate properly.

(Vision Sensing) 1. The process of examining a part to match the part to a known "good" reference. 2. A specific file or program run in the vision software to look at a specific part. Also known as a recipe.

(Machine Safety) The degree to which a circuit, system or device can be expected to perform unimpaired an anticipated function in the event of a fault. Integrity depends on several characteristics including fault tolerance, fault exclusion, risk reduction, reliable and well-tried components, well-tried safety principles, and other design considerations.

Degree of strength of electricity, light, heat, or sound per unit area or volume.

Connections and interactions between hardware and software. Hardware interfaces include serial, USB, Ethernet, RS-485, RS-232. Software interfaces include operating systems, network protocols and drivers

Overlapping of two or more waves resulting in a new wave pattern.

(Machine Safety) A guard or barrier interfaced with a machine control system so as to restrict access to or prevent inadvertent access to the hazard.

(Machine Safety) a Lockout condition due to an internal safety system problem.

In sensing logic schemes, an interrogate signal allows the information from one or more other inputs to be recognized by the inspection or control logic. Also called "gate" or "enable."

A design technique applied to electrical equipment, such as sensors, switches, and wiring for hazardous locations. The technique involves limiting energy to a level below that required to ignite a specific hazardous atmosphere. Intrinsic safety design often eliminates the requirement for explosion-proof enclosures. (Also see "NAMUR".)

A protective component designed to limit the voltage and current in an explosive area. The barrier functions outside of the explosive location to divert abnormal energy to ground.

The intensity of radiated energy (such as light energy emitted from a photoelectric sensor, or sound energy emitted from an ultrasonic sensor) falls off by an amount equal to the square of the increase in distance from the source. For example, if the distance from the energy source is doubled, the intensity of the energy decreases to one-fourth of the original strength. Or, if the distance from the source is increased ten-fold, the resultant energy becomes 1/100th of the original strength. The ratio of intensities (I) of emitted energy at distances Da and Db is: Ia/Ib =(Db)2/(Da)2

Analog photoelectric sensors provide a variable voltage or current output signal that is inversely related to and decreases with the strength of the light signal. Also known as negative slope. The relationship between output and received light signal intensity is determined by the wiring configuration.

Internet Protocol address. Address of a computer attached to an IP network (TCP/IP network). Written as four sets of numbers separated by periods. Every client and server station must have a unique IP address.

A rating system established by the IEC standards 144 and 529 which defines the suitability of sensor and sensor system enclosures for various environments. Similar to NEMA ratings for enclosures.

Industrial, Scientific and Medical band. Part of the radio spectrum that does not require a license for use.

(Machine Safety) Acronym for the International Organization for Standardization, a global federation of national standardization bodies each representing one country, that sets standards in many businesses and technologies.