What are Vision Sensors?

Companies throughout many different industries including food and beverage, automotive, electronics, logistics, and transportation rely on vision sensors daily to perform inspections to ensure the quality of their products and packaging are up to standards.

Vision sensors, not to be confused with the digital sensors found within cameras, are a type of machine vision solution meant to perform simple presence/absence checks and provide pass/fail inspections in unstructured situations. The ability of a camera to take images is combined with the processing capacity of a computer to output results regarding the location, quality, and completeness of a produced part or product. Unlike other types of sensors, including fiber optic and ultrasonic sensors, vision sensors can handle multiple inspection points per target. Vision sensors can also detect products or packages by pattern, feature, and color.

What are Sensors?

Sensors can fall into a few different categories including fiber optic, proximity, ultrasonic, photoelectronic and vision. These sensors are used in work cells to gather data for inspection or to activate other devices during production. Low-cost photoelectric sensors can perform only a limited number of simple tasks, such as position verification and basic counting. These sensors cannot distinguish between patterns or colors unlike vision sensors which have that capability. These sensors also cannot handle misalignment or inconsistency common in most work cells. In some cases, different types of sensors act as complementary technologies. For example, photoelectric sensors may be used together with vision sensors to transmit if a part is on its way to activate the camera in a machine vision system.

What are Vision Sensor Capabilities?

Although point source sensors must be exactly aligned to work, vision sensors are built to withstand a wide range of environmental variations. This enables operators to employ them in pre-configured cells without requiring a variety of costly and time-consuming adjustments. Sensors for vision can:

• Increase flexibility
• Run multiple inspection styles inside a single picture
• Produce more detailed data for quality and process improvement
• Accommodate misalignment of the handle

Benefits of Using Vision Sensors

When considering vision sensors, you may wonder what the benefits are to using this type of sensor when comparing it to other common sensors.

1. Identify features that photoelectronic sensors cannot 

Vision sensors can handle misalignment and inconsistency which allows parts to be inspected at any position on the production belt without costly or time-consuming changes having to be made to the line.

2. Enhance illumination, brightness, and image contrast

To create clearer images and improve consistency of results, vision sensors can be equipped with flexible lighting and filter options.

3. Manage misalignment and irregularity 

Vision sensors can identify objects regardless of their speed or position on the line.

4. Increase ease of use

Guided setup and programming with built-in Ethernet communications to allow users to communicate results with other systems.

How do vision sensors differ from vision systems? 

Selecting the right machine vision solution generally depends on the application’s requirements, including development environment, capability, architecture, and cost. In some cases, vision sensors and machine vision systems may both be able to satisfy an operation’s needs, but different models are designed to meet varying price and performance requirements.

Due to their strong vision algorithms, industrial-grade hardware, and high-speed picture capture and processing, vision sensors are like machine vision systems. They are both intended to do intricate jobs on high-speed production lines. And, while they both do inspections, they are designed for distinct purposes. While machine vision systems handle guiding and alignment, optical character recognition, code reading, and gauging and metrology, vision sensors are specifically designed to detect the presence or absence of parts and produce simple pass/fail responses. Vision sensors are also characterized by their ease of use and speed of deployment.

Vision sensors lack the most advanced vision tools found on independent machine vision systems, yet they can perform a wide range of vision jobs in industrial automation and logistical settings. Vision sensors are also less expensive than machine vision systems and require less knowledge to operate.