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Reliable object detection with laser, LED or infrared light

DTECT® Presence: Light barriers & photoelectric diffuse sensors

The photoelectric diffuse sensors and light barriers in our DTECT® Presence Series operate using highly developed laser technology and LEDs. Small, precise laser-light spots enable exceptionally accurate small-part detection in automated systems. 

Various sensor principles are available for different installation situations and requirements, including photoelectric through-beam sensors, photoelectric retro-reflective sensors, photoelectric diffuse sensors, and sensors with background suppression. We would be pleased to assist you personally as you search for the ideal solution for your application.

Selection guide: Which light barrier sensor do you need?

Photoelectric through-beam sensor, fork sensor, photoelectric retro-reflective sensor, photoelectric diffuse sensor or a sensor with background suppression (BGS) – every option offers its own advantages and properties. The sensor principles differ primarily in terms of range, installation effort, and behavior in relation to the background or object surface. There is a suitable principle of operation for every area of application. 

DTECT Presence Beam

DTECT® Presence Beam

Photoelectric through-beam sensors for long ranges

Photoelectric through-beam sensors operate using a separate emitter and receiver that are installed opposite each other. The direct light beam accommodates very long ranges as well as precise and interference-free detection, even in the presence of dust, steam, ambient light or challenging ambient conditions. What's more, detection is independent of the material, shape or surface of the object.

DTECT Presence Fork

DTECT® Presence Fork

Fork sensors for precision small-part detection and counting tasks

Fork sensors combine the emitter and receiver in a single sensor housing. This means the light beam is aligned exactly and no adjustment is required, which makes the installation exceptionally easy. Thanks to precision beam guidance, fork sensors reliably detect even the smallest parts starting at 0.2 mm and are ideal for small-part detection, counting tasks, or rotational speed measurements – even in systems with strong vibrations or constricted installation situations.

DTECT Presence Reflect

DTECT® Presence Reflect

Photoelectric retro-reflective sensors with reflector for easy installation

Photoelectric retro-reflective sensors combine the emitter and receiver in a single housing and employ a reflector to return the light beam. This provides space-saving installation and makes them useful for diverse applications. They enable reliable detection, even with shiny, dark or transparent materials, and offer versatile adjustment possibilities.

DTECT Presence Energetic

DTECT® Presence Energetic

Photoelectric diffuse sensors for flexible object detection

Photoelectric diffuse sensors detect the presence of objects directly by means of the light reflected from the object and require no additional reflector. They are particularly suitable for applications with stable illumination conditions and enable precise detection when colors, materials, and surfaces remain consistent.

 

DTECT Presence Energetic: FT 25-RGB1

DTECT® Presence Energetic

Contrast sensors for easy printed mark detection

Contrast sensors detect the smallest differences in color and gray values on surfaces and are particularly suitable for applications in which simple printed marks, labels, and tags must be evaluated. Depending on the sensor type, different light sources are used: either monochrome LEDs (e.g. red, green or blue) or white light with a broad light spectrum.

 

DTECT Presence Background

DTECT® Presence Background

Photoelectric diffuse sensors with background suppression for defined detection areas

Photoelectric diffuse sensors with background suppression (BGS) specifically detect objects at a defined distance from the sensor and actively suppress disruptive backgrounds. This makes them particularly suitable for applications with changing illumination conditions as well as reflective backgrounds, and increases both the detection accuracy and the process stability.

 

A comparison of four sensor operating principles: Which one is the best choice?

The following overview shows you at a glance which sensor solution is best suited for your application.

Sensor version
Components required
Properties
Advantages as compared to other sensors
Ideal solution for

DTECT® Presence Beam

Photoelectric through-beam sensor

  • Emitter
  • Receiver 
  • Emitter and receiver are placed opposite to each other
  • The interruption of a light beam is detected
  • Reacts to an actual interruption of the light beam
  • Long range
  • Great distances
  • Strong ambient light interference
  • Contaminated environment

DTECT® Presence Reflect

Photoelectric retro-reflective sensor 

  • Sensor
  • Reflector
  • It is possible to detect the interruption of a light beam
  • Long range
  • Simple adjustment and putting into operation
  • Only one reflector is required
  • Easy installation
  • Use is often possible without teach-in
  • Autocollimation: no blind zone, emitter and receiver on one axis
  • Low budget
  • No adjustment on the receiver
  • Transparency detection (FR 25-RGO)
  • Autocollimation: measurement through boreholes or apertures (FR 25-RLO)

DTECT® Presence Energetic

Photoelectric diffuse sensor 

  • Sensor
  • Detects objects solely by means of reflected energy
  • Works without a reflector
  • Teach-in is always necessary
  • Easy alignment
  • Compact solution for confined spaces
  • High contrast between OK and NOK

DTECT® Presence Background

Sensor with background suppression 

  • Sensor
  • Object detection by distance qualification
  • Reliably suppresses backgrounds
  • With Detect-All mode, also suitable for highly reflective or changing objects
  • With changing backgrounds
  • Objects that appear in an area at a defined distance from the sensor

DTECT® Presence Fork

Fork sensor 

  • Sensor
  • Sender and receiver are a thru‑beam light barrier, pre‑aligned in a single housing.
  • Easy implementation
  • Responds to interruptions of the light beam
  • Small part detection

The advantages of our DTECT® Presence photoelectric diffuse sensors

  • Reliable and precise object detection, with laser or LED
  • Flexible adjustment using teach-in, potentiometer, control line or fixed presettings
  • IO-Link capable sensors for easy parameter configuration and integration
  • Different sizes, ranges and switching variants, for nearly every installation situation
  • Reliable object detection even with transparent materials or challenging surfaces

DTECT® Presence Key Visual
BlueLight - The NEW standard

Detect more, do more in industrial automation.

BlueLight technology for optical sensors 

The BlueLight technology employs shortwave, high-energy blue light to enable reliable detection of dark, shiny or semi-transparent objects. This approach improves detection stability in automated processes – ideal for applications in which classic red light sensors reach their limits.

More about BlueLight

IO-Link sensors: For intelligent networking

IO-Link creates a standardized digital interface between sensors, actuators and the control system. This allows faster device configuration, transparent monitoring of states and reliable transmission of process data – for stable processes and efficient, networked production.

More about IO-Link

Themenbanner IO-Link

The Power of 3: Three sensors for 99% of your applications

The "Power of 3" puts an end to the time-intensive search for the perfect individual sensor. Whether shiny metal parts, deep black packaging, or transparent PET bottles, with our many years of experience, we have bundled the essence of industrial object detection into three compact sensors that reliably carry out 99% of your tasks.

More about The Power of 3

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Typical applications for photoelectric diffuse sensors & light barriers

Photoelectric diffuse sensors and light barriers are used in industrial automation wherever reliable object detection is required. They facilitate stable production operations and automated material flows – even with varying object distances or changing ambient conditions.

Depending on the application, utilize the strengths of the various different sensors in the DTECT® Distance Series. Several typical examples and suitable sensor solutions are provided below. 

Loading robot-controlled test stations

In automated test stations, components must be detected with process reliability and positioned correctly. Photoelectric diffuse sensors monitor the presence and position of the components and ensure that only correctly inserted parts are processed further. This prevents incorrect loading

Palletizing packaging in feeding systems

In packaging and palletizing systems, packages must be detected reliably so that robots can grip and position them correctly. Photoelectric diffuse sensors or light barriers detect incoming objects, enabling a continuous, automated material flow without interruptions.

DTECT Presence Energetic: FT 25-RGB1

Detection of printed marks in the printing and packaging industry

In packaging systems, printed marks must be detected with precision in order to position material webs correctly or trigger cutting and labeling processes. Contrast sensors detect even the smallest differences in gray values, enabling precise alignment and positioning even at high process speeds.

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Distance sensors for all measuring tasks: Triangulation sensors, time-of-flight sensors with IO-Link

DTECT® Distance

Photoelectric through-beam sensors operate using a separate emitter and receiver that are installed opposite each other. The direct light beam accommodates very long ranges as well as precise and interference-free detection, even in the presence of dust, steam, ambient light or challenging ambient conditions. What's more, detection is independent of the material, shape or surface of the object.

 

DTECT® Color

Detect the finest color differences, printed marks, and labels reliably with our color sensors – ideal for fast production processes in packaging, printing, and industrial applications.

SensoPart People - Anwendungsberatung

Application consulting

Start your automation project with our technical consulting service and work with our experts to develop a sensor solution that is tailored exactly to your application. We are happy to be there for you

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