To maximize embedded camera systems in industrial applications, lens selection is essential. By directing light onto the imager, a suitable lens guarantees that the camera produces sharp, detailed images. Lens selection affects productivity, decision-making, and product quality in industries like manufacturing, healthcare, and surveillance. To ensure compatibility, performance, and return on investment, this guide outlines important lens selection criteria.
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Considerations for lens selection:
1. Lens Format: Ensuring Compatibility with Image Sensors
The lens format determines its compatibility with the camera sensor. Ensuring that the sensor image format and the lens format match is essential for avoiding issues like vignetting or wasted sensor area. However, situations often arise where the exact match is unavailable due to application-specific requirements like field of view (FOV), resolution, or focal length.
Here’s the lens selection rule:
Larger format lenses can be used with smaller sensors without issues.
Smaller format lenses cannot cover larger sensors, leading to reduced image quality and missed details.
For instance, when working with the Sony IMX290 sensor (1/2.8” format), you can choose a lens with a 1/2.8” format or larger, such as 1/2.5” or 1/2.3”. Similarly, with the AR0521 sensor (1/2.5” format), use a lens of the same size or larger. This ensures full utilization of the sensor's surface area, providing optimal image clarity.
2. Focal Length: Defining Focus and Clarity
Focal length is a fundamental property of lenses, indicating the distance between the optical center of the lens and the imager plane where light converges. This measurement significantly impacts the field of view and image magnification.
Short focal lengths provide a wider field of view, making them suitable for applications like surveillance or wide-area monitoring.
Longer focal lengths offer narrow fields of view but greater detail and magnification, ideal for industrial inspections or medical imaging.
For instance, in a factory automation setup, selecting a lens with an appropriate focal length ensures that conveyor belts are fully covered without missing critical product details.
Visualizing focal length helps streamline lens selection for specific use cases, whether it's a broader perspective or a zoomed-in, detail-oriented image.
3. Field of View: Capturing the Desired Scene
The field of view (FOV) determines the area captured by the camera. While FOV and angle of view are often used interchangeably, they differ in application:
The angle of view is a lens property and remains constant for a specific lens.
Field of view is determined by the camera-lens combination, influenced by both the lens format and the sensor format.
When the lens format is larger than the sensor format, the field of view becomes narrower than the angle of view, limiting the area captured. Conversely, using a smaller format lens with a larger sensor results in suboptimal image quality due to unused sensor areas.
For example, a lens with an 80-degree angle of view on a 1/3” sensor will provide an 80-degree FOV. However, if the sensor is smaller (e.g., 1/3.2”), the FOV will be reduced, affecting image coverage. Lens selection must account for this interaction to achieve the desired results.
4. Lens Mount: Aligning Mechanical Standards
The lens mount defines how the lens attaches to the camera module. Common standards include:
C-Mount and CS-Mount: Popular in industrial applications, offering high resolution and versatility.
M12 (S-Mount): Compact and cost-effective, ideal for embedded systems and small devices.
M6 and smaller: Common in mobile or ultra-compact devices.
Each mount type supports a range of focal lengths, FOVs, and depth-of-field requirements, making it crucial to align the mount with the application’s mechanical and optical specifications. Proper lens selection at this stage ensures seamless integration with existing hardware, avoiding additional costs or design changes.
Best Practices for Lens Selection
To streamline the lens selection process for embedded cameras, consider the following:
Define the Application: Determine whether the priority is resolution, FOV, or cost-effectiveness based on the end-use case.
Match Lens and Sensor Formats: Ensure compatibility while following the larger-lens rule for flexibility.
Consider Environmental Factors: For harsh environments, opt for ruggedized lenses with protective coatings.
Test with Prototypes: Validate the lens performance in real-world scenarios to fine-tune the choice.
The Business Impact of the Right Lens Selection
For industrial sectors, selecting the right lens impacts more than just image quality. It enhances operational efficiency, reduces downtime, and enables real-time decision-making. For instance:
In manufacturing, it ensures high-quality inspection, reducing product defects.
In healthcare, it enables precise imaging for diagnostics.
In surveillance, it provides comprehensive coverage with fewer blind spots.
By optimizing lens selection, businesses can improve ROI, streamline processes, and meet industry standards for quality and efficiency.
Learn how to enhance lens selection for embedded cameras and improve your industrial systems with our Vision Engineering services.
Optimizing Lens Selection for Embedded Cameras
For embedded cameras in all industries, choosing the appropriate lens is essential to getting the performance that is sought. Factors like lens format, focal length, field of view, and lens mount play an essential role in ensuring compatibility and image quality. At Regami Solutions, we specialize in guiding businesses toward the ideal lens for their applications, whether it’s industrial automation, medical imaging, or surveillance.