Choose a borescope lens by matching its field of view, focus range, and viewing direction to the target’s size, distance, and position—not by selecting the widest view or shortest focus specification alone. A wide field of view can show more of a nearby area, while a narrower view may make details easier to inspect at a distance. The correct viewing direction determines whether the lens looks forward, to the side, or at an angle. Before ordering, confirm how the supplier defines each specification and whether the lens is compatible with your borescope.
For more information, please visit our website.
Before comparing lenses, describe what the borescope must reveal and where the lens must reach. A buyer inspecting a broad internal surface may prioritize coverage, while an inspection for small cracks, pits, or edge damage may require a clear, appropriately framed close-up. Access restrictions also matter: bends, narrow openings, and nearby walls can limit the angle from which the lens can see.
Record the target’s approximate distance from the lens, its dimensions, and whether it lies ahead of the insertion tube or beside it. Note whether the inspection involves one fixed point or multiple areas along a route. These observations help you give suppliers a useful application brief instead of requesting a lens based on a single specification.
Field of view (FOV) describes the angular extent of the scene visible through the lens. It is commonly specified in degrees, but suppliers may report horizontal, vertical, or diagonal FOV. Ask which convention applies before comparing figures, because values measured in different ways are not directly equivalent.
A wider FOV can capture more of the surroundings at a given working distance, which may help with orientation or scanning a broad surface. However, the target occupies a smaller part of the image when more of the scene is included, so fine features may be harder to inspect. A narrower FOV can frame a smaller area more closely, but it may require more repositioning to cover a larger surface.
For example, a 60° FOV and a 90° FOV are useful comparison points when discussing options with a supplier, not universal recommendations or guaranteed product specifications. Ask for the expected view at your actual working distance, and, where possible, review a representative image or optical drawing. This gives you a more practical basis for judging coverage than the angle alone.
Focal length is an optical design parameter that affects how a lens forms an image. In borescope purchasing, the more immediately useful information is often the focus range or working distance: the distance range over which the target can appear acceptably sharp. Suppliers may use different terms, so ask them to define the measurement and state whether it refers to the lens face or another reference point.
A lens intended to focus at close range may be suitable for nearby features, but it may not show a target clearly when held farther away. Conversely, an optic focused for a more distant target may not provide the close-up detail your inspection requires. The right choice depends on the distance you can maintain in the actual inspection, not simply on which specification appears larger or smaller.
Measure or estimate the space between the lens and the area of interest, including any practical limits imposed by the access path. If the target distance varies, tell the supplier the expected range rather than giving only one nominal value. For instance, describe a hypothetical inspection requiring useful focus from 5 mm to 20 mm if that reflects your application; these figures are an example to communicate a requirement, not a claim about a particular lens.
Viewing direction describes where the borescope lens looks relative to the insertion tube. A forward-viewing lens looks along the direction of travel and can help inspect a path ahead. A side-viewing lens looks across the tube’s axis and can help examine walls or features that are difficult to see by looking straight forward.
Coantec are exported all over the world and different industries with quality first. Our belief is to provide our customers with more and better high value-added products. Let's create a better future together.
An oblique view sits between these orientations and may be useful when a target is neither directly ahead nor perpendicular to the tube. A commonly used geometric reference for side viewing is 90° to the insertion direction, but confirm the supplier’s definition and the image orientation. The viewing angle and field of view are separate specifications: one describes direction, while the other describes the width of the visible scene.
Choose the direction based on the path the borescope can follow and the surface you need to inspect. A forward view can be less effective when the critical area is on a side wall, while a side view may not show what lies directly ahead. If an inspection includes both orientations, ask whether interchangeable optics or another compatible configuration is available rather than assuming a single lens will meet both needs.
Optical fit is only one part of selection. Confirm the borescope model, lens interface, probe diameter, and any mechanical limits that affect installation or access. Also establish whether the lens is fixed or interchangeable and whether replacing it affects the system’s intended use or configuration.
Ask how the image is oriented on the display and whether the view matches the way operators expect to interpret the target. If you need to compare images over time, specify the required framing and viewing direction in your inspection procedure. These details can reduce confusion during quotation and help the supplier recommend a configuration that fits the equipment and task.
Prepare a short application brief before requesting a quotation. Include the borescope model, target material or component type, access route, approximate target dimensions, expected lens-to-target distance, and preferred viewing direction. Add photographs, sketches, or a simple layout when available, while avoiding sensitive information that is not needed to assess the configuration.
Ask the supplier to confirm the FOV convention, focus or working-distance range, viewing angle, physical compatibility, and any available drawings or sample images. If more than one lens configuration may work, request a comparison against the same inspection requirements. A documented comparison makes it easier for purchasing, engineering, and inspection teams to evaluate the same criteria.
Coantec can review your application requirements and help assess suitable borescope lens configurations within its available product range. To make the discussion productive, share the borescope model or interface details, your target distance, the area to be viewed, and whether you need forward, side, or oblique viewing. Coantec can then confirm relevant specifications and compatibility for the configuration under consideration.
For B2B sourcing, also clarify the intended inspection environment, expected order quantity, and any documentation or customization requirements. Availability, compatibility, and lead time depend on the specific configuration and should be confirmed during quotation. This approach helps buyers compare options based on the inspection task rather than relying on a headline specification alone.
To choose a borescope lens, first define where the target is and how far the lens can be positioned from it. Then match field of view to the desired balance between scene coverage and detail, verify the working-distance or focus range, and select the viewing direction that exposes the target. Finally, confirm measurement conventions and physical compatibility with the supplier.
Your next step is to send Coantec the borescope model, target distance, target dimensions, access constraints, and preferred viewing direction for a configuration review. These details provide a practical basis for comparing lens options and confirming whether a proposed lens suits your inspection application.
If you want to learn more, please visit our website Borescope Lens.