Views: 0 Author: Site Editor Publish Time: 2026-08-07 Origin: Site
Field of view determines how much of the cavity or target area an endoscope camera can show at one time. Lens distortion describes how accurately the image preserves the geometry of that scene. A wider field of view can reduce blind areas and help operators orient the probe, but it can also make objects appear smaller, stretch edges or introduce barrel distortion. The correct design is therefore not the widest available lens. It is the lens that provides enough coverage while preserving the detail, working distance and geometric accuracy required by the device. OEM teams should compare diagonal, horizontal and vertical coverage, then test the final lens and camera structure on the real target.
Field of view may be stated as diagonal, horizontal or vertical. These values are not interchangeable. A diagonal value is normally the largest number, but a device often cares more about horizontal wall coverage or vertical clearance. When comparing modules, confirm which direction the number represents and whether the output image is cropped by the sensor mode or host software.
Wider FOV Advantage | Possible Trade-Off | Project Question |
More cavity coverage | Objects occupy fewer pixels. | Is broad orientation or fine defect recognition more important? |
Fewer blind areas | Edge stretching or barrel distortion may increase. | Must geometry or dimensions remain visually accurate? |
Easier probe navigation | Reflections and LED hot spots can enter the frame. | Will the surface be shiny, wet or curved? |
More context at close range | Lens design may increase head size or reduce edge detail. | What is the maximum camera-head diameter? |
Barrel distortion bends straight lines outward and is common in wide-angle optics. In a pipe, cavity or engine cylinder, this may be acceptable when the goal is general observation. It becomes more important when the device needs consistent geometry, comparison between images, edge inspection or measurement-related analysis. Software correction can reduce visible distortion, but it may crop the image, resample pixels and add processing requirements.
Application Need | Preferred Direction | Main Risk to Check |
Small close-range medical visualization | Moderate or wide coverage with controlled edge behavior. | Reflections, color shift and loss of fine detail. |
Pipe or cavity navigation | Wide coverage to reduce blind areas. | Barrel distortion and small target appearance. |
Side-wall defect inspection | Side-view geometry matched to lateral working distance. | Uneven focus and illumination across curved surfaces. |
Documenting repeatable features | Controlled distortion and stable image scale. | Cropping or digital correction changing the image. |
SincereFull provides several field-of-view directions that can support different evaluation paths. The SF-SAC1010USB-D3.0-PLUS-D121 uses a 121-degree diagonal direction for broad close-range coverage. The SF-C1019USB-D3.5-PLUS-D90-XYD01 V1.1 provides a 90-degree direction for a more controlled viewing range. The SF-YL0320-V1 + SF-N735-FT-V2 is listed with an 88-degree direction. The autofocus SF-SP12-D12.5 and SF-SP12-D14.5 use an 80.9-degree diagonal lens direction. These numbers should be evaluated together with working distance, distortion, target detail and the final output crop.
1. Define the minimum area that must be visible at the normal working distance.
2. Measure the real target width and distance rather than selecting by angle alone.
3. Check center and edge resolution on the actual target surface.
4. Inspect straight lines, circular holes and repeated patterns for distortion.
5. Test with final LED brightness and protective window or shell.
6. Confirm the host software does not crop, scale or correct the image unexpectedly.
7. Record whether the project values orientation, defect recognition or geometry most.
A medical endoscope camera module may need broad visualization in a very small head while maintaining controlled color and reflections. An industrial borescope or inspection endoscope may prioritize side-wall coverage, long-cavity navigation or visibility of cracks and deposits. Both applications can use wide-angle optics, but the acceptance criteria should be defined by the device task rather than by the largest FOV number.
Is a 120-degree lens always better than an 80-degree lens?
No. A 120-degree lens shows more area, but the same target may occupy fewer pixels and edge distortion may be stronger. An 80-degree lens may provide a more concentrated view. The better choice depends on working distance and the size of the feature that must be observed.
Why do straight lines look curved in an endoscope image?
Wide-angle lens distortion can bend lines, especially near the image edge. The effect may also change with lens position, protective windows and software correction. Evaluate the complete assembled camera.
Can distortion be corrected by software?
Yes, distortion correction can be applied when calibration data and processing resources are available. However, correction may crop the image and interpolate pixels. It should not replace a suitable optical design.
Does field of view change with resolution?
The optical lens defines the available image circle, but the active sensor mode or software crop can change the displayed coverage. Different resolution modes may therefore show different effective fields of view.
What FOV is suitable for a side-view endoscope camera?
There is no universal number. The lateral working distance, pipe diameter, wall curvature and required defect size should determine the target coverage. Side-view testing should include edge focus and light uniformity.
Can SincereFull evaluate a custom lens angle?
Lens, field of view, focus, distortion, LED and shell options can be evaluated for the project. Feasibility depends on sensor size, camera-head diameter, target distance and required image quality.
Send the application, target size, working distance, preferred viewing direction and camera-head limit to SincereFull. We can help compare suitable FOV and lens directions for project evaluation.
Note: This article is for device design and camera module selection reference. Final medical device compliance should be evaluated according to the target market, application and applicable regulations.
