Precise control and synchronisation of lighting in industrial vision systems. Our Machine Vision Controllers ensure constant light output, precise trigger logic and stable high-speed processes – tailored to the camera, optics and application.
Machine vision controllers control and regulate LED lighting in industrial image processing systems. They ensure a stable constant current supply, enable precise strobe operation and synchronise lighting and camera via defined trigger signals. In doing so, they form the basis for reproducible image quality – particularly in fast or demanding inspection processes.
At STEMMER IMAGING, you don’t receive controllers in isolation, but rather tailored to your entire system architecture. As a manufacturer-independent supplier, we combine high-performance products from leading brands with in-depth engineering expertise. In this way, we ensure that power output, number of channels, trigger logic and integration interfaces are precisely matched to the lighting, camera and application – technically sound and practice-oriented.
Machine vision controllers precisely control LED lighting in continuous or strobe mode and synchronise light pulses with camera and trigger signals. They are a central component of reproducible image processing systems – particularly at high speeds, with short exposure times or in complex multi-channel setups.
This guide explains the most important selection criteria and shows you how to systematically use the relevant filters in STEMMER IMAGING’s product finder.
The number of channels defines how many lighting units can be controlled independently of one another. A single-channel controller is suitable for simple systems with a single light source. Multi-channel controllers enable the separate control of multiple lighting units within a system.
Note:
A single channel is sufficient for simple inspection tasks with ring or spot lighting.
Two to four channels are typical for combined lighting concepts, such as incident light + dark field or multiple lighting directions for contrast optimisation.
Eight or more channels are used in complex systems with sequential control or multiple inspection stations – for example, when several lighting angles are activated in succession for each image.
Plan for expandability: A later system expansion is significantly easier if sufficient channels are available.
Product filter:
In the “Number channels” field, select the required number of channels according to your lighting architecture.
The maximum trigger frequency specifies how quickly the controller can trigger light pulses. It is particularly relevant for strobe applications and high-speed processes.
Note:
Stationary test stations often operate at frequencies below 100 Hz.
Classic area-scan camera applications typically operate between 100 Hz and 5 kHz.
High-speed processes, such as those in the electronics or packaging industries, often range between 5 kHz and 50 kHz.
Line scan camera or web inspection systems may require trigger frequencies ranging from 50 kHz to over 100 kHz.
In addition to the maximum frequency, temporal jitter is crucial. Even deviations in the range of a few microseconds can cause visible intensity fluctuations with short exposure times.
Product filter:
Use ‘Max. trigger frequency (Hz)’ to select controllers that match the dynamics of your application.
Weight plays a role in the mechanical integration of the controller, particularly in confined installation spaces or moving systems.
Note:
Typical controllers range from a few hundred grams to less than one kilogram.
In control cabinet solutions, this is usually not a critical factor. However, in decentralised mounting on machine frames or in moving units, a lower weight can reduce mechanical stress.
Product filter:
You can use “Weight (kg)” to narrow down controllers according to your mechanical requirements.
The output power per channel determines whether the connected LED lighting can be adequately powered.
Note:
Small spotlights or ring lights often require power in the range of 5–30 W per channel.
Compact panel or line lights typically range from 30–100 W.
High-power line lights for railway inspections may require power ranges exceeding 100 W per channel.
In pulsed operation, LEDs are often driven at 2 to 5 times the current level compared to continuous operation. Typical pulse durations range from 5 µs to 5 ms. The combination of pulse duration, repetition rate and thermal reserve is crucial.
A power reserve of around 20–30% increases process stability and reduces thermal stress.
Product filter:
Use the “Max. output power per channel (W)” filter to select controllers that match the power consumption of your lighting.
The intensity control method influences the precision and stability of the brightness setting.
Note:
For simple applications with constant lighting, a fixed setting is sufficient.
In measurement and inspection systems with varying products or materials, reproducible digital intensity control is required.
Typical requirements include brightness adjustments within a range of a few percentage points or rapid switching between several stored intensity values when changing recipes.
In precision measurement systems, the stability of the intensity is often more important than the maximum brightness.
Product filter:
Select the appropriate control method under “Intensity control method”.
The interface defines how the controller is integrated into your vision system.
Note:
Simple stand-alone systems often use direct trigger signals or local operation.
In automated systems with multiple cameras or central recipe management, serial interfaces or Ethernet-based communication are common.
In networked systems, software-based parameterisation simplifies the management of multiple lighting channels and reduces commissioning times.
Product filter:
Use the ‘LED controller interface’ filter to select controllers that are compatible with your system architecture.
Depending on the model, controllers support continuous light, strobe or combined operating modes.
Note:
Continuous light is suitable for exposure times in the range of 1–10 ms for stationary or slow-moving objects.
Pulse mode is used when motion blur needs to be reduced. Typical pulse durations range from 5 µs to 500 µs in high-speed applications.
At very high conveyor speeds, a combination of short pulse duration and high repetition rate may be required.
Product filter:
Select the desired operating mode under “Operating mode” to identify suitable models.
Some controllers support Triniti technology for advanced control of lighting systems.
Note:
Such technologies can simplify integration into complex vision systems and offer additional configuration options. This can be particularly advantageous for multi-channel or programmable applications.
Product filter:
You can use the “Triniti” filter to select controllers that support this technology.
STEMMER IMAGING offers controllers from various manufacturers and series.
Note:
The choice of manufacturer may depend on existing system standards or integration preferences. However, the decisive factor remains technical compatibility with your performance and integration requirements.
Product filter:
You can use the “Manufacturer” filter to narrow down the range.
Use the product filter to quickly identify suitable controller models – or contact us if you need assistance with technical specification.
Benefit from our value-added services which we match to your individual requirements.
An external controller is necessary as soon as the lighting needs to be actively controlled or synchronised. This applies in particular to applications with pulsed operation, variable intensity or precise trigger synchronisation with the camera. In simple continuous-light setups, a fixed power supply may be sufficient – however, for dynamic or high-speed processes, a dedicated controller is essential for reproducible results.
With short exposure times, the light pulse must fall precisely within the image capture window. Even slight timing deviations can lead to fluctuations in brightness, loss of contrast or inconsistent measurement values. In systems with multiple cameras or clocked processes, timing stability is a key determinant of the system’s overall performance.
In pulse mode, LEDs are briefly operated at a higher current to achieve high light intensities. The correct coordination of current, pulse duration and repetition rate is crucial here. If thermal limits are exceeded, this can reduce the service life of the lighting or lead to unstable light output. A suitable controller limits these parameters in a controlled manner and ensures safe operating conditions.
In fast-moving processes – such as continuous motion or line-scan camera systems – light pulses must be triggered at a high repetition rate with minimal temporal jitter. The trigger frequency alone is not sufficient: temporal precision is crucial. Only when the camera, motion and lighting are precisely synchronised do contrast and measurement accuracy remain constant.
A sufficient power reserve ensures stable brightness even under varying process conditions. If a controller is operated continuously at its limit, intensity fluctuations may occur or thermal protection mechanisms may be triggered. A technically well-dimensioned reserve therefore not only increases process stability but also extends the service life of the lighting.
Yes. Depending on the interface, controllers can be integrated into higher-level control systems, configured centrally or synchronised with multiple cameras. In networked architectures, this simplifies recipe management, system diagnostics and the scaling of complex systems.
A multi-channel controller is required when several light sources need to be controlled independently or sequenced over time. This is the case, for example, when different lighting directions are used to optimise contrast or when several inspection stations are operated within a single system. Separate channel control increases flexibility and simplifies future expansions.
