Machine Vision Lens for Fruit and Vegetable Grading Machines: How to Inspect Size, Shape and Visible Quality at High Sorting Speed

Fruit and vegetable grading machines must inspect natural products that vary continuously in diameter, length, curvature, surface appearance, orientation and position. Unlike manufactured components, fresh produce does not arrive with perfectly repeatable geometry. Apples can rotate differently from one carrier to another, potatoes can present irregular contours, tomatoes can vary significantly in diameter, citrus fruit can occupy different heights above the conveyor, and vegetables such as onions, peppers or cucumbers can present very different aspect ratios. For machine builders, Machine Vision Lens selection therefore has to be based on the complete grading envelope rather than one nominal product size.

Buyers searching for a machine vision lens for fruit grading machine, vegetable sorting camera lens, produce grading machine vision lens, fruit size inspection camera lens, industrial camera lens for food sorting machine, machine vision lens for apple grading, camera lens for potato sorting, tomato grading machine vision lens or high-speed produce inspection lens should begin with product range, carrier pitch, number of lanes, camera field of view, smallest visible quality feature, sensor format, working distance and line speed. Focal length becomes useful only after these machine parameters are defined.

The current Kyptec Automation® Machine Vision Lens collection includes conventional Machine Vision Lenses across 5 MP, 10 MP and 25 MP resolution classes with multiple focal lengths and sensor-format options. The range is positioned for high-resolution industrial imaging, low distortion, consistent focus and high-speed inspection, and Food/Beverage Processing is explicitly listed among the major application areas on current product pages. This gives fruit and vegetable grading-machine OEMs practical options for broad multi-lane views, medium inspection fields and higher-detail or increased-working-distance stations.

Fruit and Vegetable Grading Lens Selection Should Begin With Product Envelope

A produce grading machine should first define the physical space occupied by the largest valid product in every expected orientation. For round fruit such as apples, oranges and tomatoes, this can be based largely on maximum diameter. For elongated vegetables such as cucumbers, carrots or peppers, the maximum rotated envelope can be significantly larger than the nominal width.

The camera field should include the product plus realistic positional tolerance, but excessive empty background should be avoided because every additional millimetre of FOV reduces pixels per millimetre.

A practical calculation is:

Pixels per millimetre = camera pixels across the relevant direction ÷ physical FOV in millimetres

If a 5,000-pixel image covers 500 mm, nominal sampling is approximately 10 pixels/mm. If the same camera covers 1,000 mm, sampling falls to approximately 5 pixels/mm. The wider field may include more fruit or lanes, but each individual product receives fewer native pixels.

Product Diameter and Shape Require Different Optical Measurements

Fruit grading systems are often expected to categorize products by size, while vegetable grading can require more complex contour information. A round apple can be represented by diameter and circularity, whereas a potato or pepper may require width, length, outline or asymmetry information.

The Machine Vision Lens should therefore preserve useful object boundaries across the entire valid field.

For size grading, low and stable optical distortion is valuable because changing geometry across the image can alter apparent dimensions if the complete camera-lens system is not properly calibrated. Kyptec Automation® describes its Machine Vision Lenses as designed for low-distortion, consistent-focus industrial imaging, which is directly relevant where machine builders need stable object geometry across multiple grading positions.

Single-Lane and Multi-Lane Graders Need Different FOV Strategies

A single-lane fruit grader can dedicate most of the camera sensor to one product or one carrier position. This can provide high image occupancy and strong pixels per fruit.

A multi-lane grader distributes available sensor resolution across several simultaneous products.

If one image covers six lanes, each fruit occupies only a portion of the full image width. This does not automatically create a problem, but the OEM must calculate whether enough native pixels remain on the smallest product and the smallest visible quality feature.

Where one camera becomes too wide, splitting the grader into two or more optical zones can provide substantially better sampling than forcing one camera to cover every lane.

Carrier Pitch Should Be Included in Camera FOV

Cup graders, roller graders and other carrier-based produce machines normally present fruit at a defined pitch. The pitch includes not only the product width but also the gap between adjacent carriers.

If a camera captures multiple carrier positions simultaneously, the unused space between products also consumes sensor pixels.

For this reason, the grading-machine OEM should calculate total FOV from the number of visible carrier positions multiplied by actual pitch, then verify pixels per product.

Reducing unnecessary multi-product coverage can significantly increase the number of pixels allocated to each fruit without changing the camera.

12 MM Machine Vision Lenses Can Support Broader Grading Fields

Where a grading machine needs a comparatively broad FOV from limited camera stand-off, a shorter focal-length class can be evaluated.

The Kyptec Automation® KL-1224 12 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens is specified as model KL-1224 with 12 mm focal length, 10 MP resolution, C-mount, 2/3" image format and F2.8–16 aperture range. Food/Beverage Processing is included among its listed major applications.

This type of lens can be evaluated for broader multi-lane grading views, wider produce conveyors or stations where the camera is physically close to the product. The final decision should always be based on the resulting FOV and pixels per smallest fruit or vegetable rather than focal length alone.

16 MM Lenses Can Balance Coverage and Product Sampling

A 16 mm focal-length class can provide a useful middle ground between very broad coverage and tighter per-product imaging.

The Kyptec Automation® KL-1226 16 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens is specified as model KL-1226 with 16 mm focal length, 10 MP resolution, C-mount, 2/3" image format and F2.8–16 aperture range. Food/Beverage Processing is also explicitly included in its application list.

For fruit and vegetable grading OEMs, a 16 mm lens can be evaluated where the system needs moderate multi-product coverage but should retain better pixels per product than a wider optical field.

Product Rotation Is Essential for Visible Quality Inspection

One camera view cannot see the entire surface of a three-dimensional fruit.

Many produce grading machines therefore rotate the fruit as it moves through the inspection region or use several camera views. This enables different portions of the surface to become visible over time.

The optical consequence is important: every camera view should maintain a controlled FOV and similar useful resolution so that visible quality information remains consistent throughout rotation.

A very wide camera used for one view and a tight camera used for another may create uneven pixels per surface feature. OEMs should therefore coordinate the lens selection across the complete multi-view architecture.

Multi-View Grading Machines Should Standardize Image Scale Where Practical

Apple graders, citrus graders, tomato sorters and other high-performance produce machines can use top, side or angled cameras.

If different views are used together for size, shape or surface analysis, maintaining similar object-side sampling can simplify system design.

This does not mean every camera must use the same focal length. Different mounting angles or working distances may require different lenses. The objective is to maintain a controlled physical scale rather than forcing identical optics mechanically.

The Kyptec Automation® Machine Vision Lens collection includes multiple focal lengths across several resolution classes, allowing OEMs to select different lenses while maintaining comparable optical performance roles. The collection currently shows 31 total lens products across the wider category.

Visible Surface Quality Depends on Pixels per Defect, Not Pixels per Fruit Alone

A fruit can occupy hundreds of pixels and still provide inadequate sampling for a small visible mark.

Machine builders should therefore separate two calculations:

pixels across the whole fruit, and pixels across the smallest visible quality feature that the machine is expected to evaluate.

If a small blemish or visible surface irregularity occupies only a few camera pixels, increasing software complexity will not recover detail that the optical system never captured.

The smallest visible quality feature should therefore influence whether the camera needs a tighter FOV, a higher-resolution lens-camera combination or several optical views.

High-Resolution Lens Architectures Can Support Larger Multi-Lane Fields

Higher-resolution optics can be useful when one camera must capture several fruit positions while retaining useful local detail.

Kyptec Automation® currently offers 25 MP conventional Machine Vision Lenses in focal lengths including 8 mm, 12 mm, 16 mm, 25 mm, 35 mm and 50 mm within its broader portfolio. A 25 MP architecture can be especially relevant where an OEM wants to image more lanes or more product positions per frame without reducing native sampling as aggressively as a lower-resolution system.

However, megapixels should not be treated as a substitute for proper FOV design. If the additional sensor resolution is immediately used to double the physical field, much of the pixels-per-product advantage can be consumed.

Product Height Variation Creates Depth-of-Field Requirements

Fruit and vegetables do not all sit at the same optical height.

Larger apples or oranges can extend closer to an overhead lens. Smaller products can sit deeper inside a cup or roller mechanism. Irregular vegetables can create even larger working-distance variation.

The Machine Vision Lens therefore needs enough usable depth of field to maintain useful sharpness across the legitimate product-height range.

Stopping down the aperture can increase depth of field, but excessive stopping can reduce light and eventually reduce fine spatial detail through diffraction. The production aperture should therefore be optimized according to fruit-height range, required detail, available illumination and exposure time.

25 MM Lenses Can Support Controlled Grading Zones

Where each camera observes a smaller number of fruit positions or the working distance is greater, a 25 mm focal-length class can be practical.

The Kyptec Automation® KL-1228 25 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens is specified as model KL-1228 with 25 mm focal length, 10 MP resolution, C-mount, 2/3" format and F2.8–16 aperture range. Food/Beverage Processing is among the listed applications.

This lens can be evaluated for tighter apple grading zones, individual fruit-size measurement, smaller lane groups or localized visible-quality inspection where the calculated FOV supports the required product range.

Product Size Measurement Should Be Validated Across the Entire Camera Field

A fruit positioned near the center of the image can appear slightly different from the same product positioned toward the outer field if distortion and perspective are not properly managed.

For grading applications, this matters because the machine may classify products by small dimensional differences.

OEM qualification should therefore include representative produce at the center, intermediate positions and outer parts of every valid camera field.

Where dimensional output is important, complete camera calibration remains necessary even when low-distortion Machine Vision Lenses are used.

Fruit Orientation Can Change Apparent Dimensions

A non-spherical product can present different apparent width depending on orientation.

Potatoes, pears, peppers and elongated vegetables are obvious examples, but even nominally round fruit can deviate from perfect symmetry.

If grading is based on size and shape, one image may not always represent the complete maximum cross-section.

The machine architecture should therefore decide whether to use controlled orientation, product rotation, multiple views or repeated measurements as the product moves.

Lens selection should be made around that actual viewing strategy.

High Sorting Speed Must Be Evaluated With Real Exposure Conditions

Fruit graders can operate at high carrier speed, and the product may also rotate during imaging.

This creates two potential sources of motion: translation through the machine and rotation around the product axis.

A lens can be perfectly focused on a stationary apple while the real production image becomes softer because the product moves during exposure.

The distance or angular movement during exposure should therefore be considered together with camera timing and illumination. Kyptec Automation® positions its Machine Vision Lenses for reliable high-speed inspection and measurement applications, making the portfolio relevant to high-throughput grading equipment.

Sorting Speed and Image Resolution Must Be Balanced at Machine Level

Increasing image resolution can increase the amount of data generated per frame. Increasing the number of camera views can increase it further.

The optical design should therefore provide enough information for the required grading decision without unnecessarily imaging large empty areas or more carrier positions than necessary.

Efficient FOV design can help both optical performance and system throughput because sensor pixels are concentrated on actual products rather than unused machine background.

35 MM Lenses Can Support Greater Stand-Off

Some grading machines have mechanical structures, protective housings or carrier systems that prevent close camera placement.

The Kyptec Automation® KL-1230 35 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens is specified as model KL-1230 with 35 mm focal length, 10 MP resolution, C-mount, 2/3" format and F2.8–16 aperture range. Food/Beverage Processing is explicitly included among its listed applications.

A 35 mm focal-length class can be evaluated for greater stand-off, narrower grading lanes or localized produce inspection where the resulting FOV is appropriate.

Multi-Lane Graders Can Benefit From Multiple Optical Zones

A wide produce grader with many lanes can sometimes provide stronger overall performance by splitting the machine into several camera zones.

For example, instead of one camera covering eight lanes, two cameras can each cover four lanes. This can increase pixels per fruit while still covering the same total machine width.

Adjacent zones should include enough overlap or boundary margin to ensure products near lane transitions remain fully visible, but excessive overlap should be avoided because it wastes sensor resolution.

Relevant Fruit and Vegetable Grading Machines for Kyptec Automation® Machine Vision Lenses

Relevant OEM machines include apple grading machines, citrus sorting machines, orange grading systems, tomato graders, potato grading machines, onion sorting machines, pepper grading equipment, cucumber sorting systems, fresh-produce optical graders, multi-lane fruit sorting machines and automated vegetable grading equipment.

For broader compatible fields, Kyptec Automation® KL-1224 12 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens and Kyptec Automation® KL-1226 16 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens can be evaluated according to actual FOV requirements. Controlled medium fields can use Kyptec Automation® KL-1228 25 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens, while increased-working-distance stations can evaluate Kyptec Automation® KL-1230 35 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens. These models belong to Kyptec Automation®'s current conventional 10 MP Machine Vision Lens family and explicitly list Food/Beverage Processing among their intended applications.

Why Kyptec Automation® Is a Strong Choice for Fruit and Vegetable Grading OEMs

Produce grading equipment benefits from an optical portfolio that can support broad multi-lane coverage, controlled individual-product views, different camera stand-offs and multiple resolution levels.

Kyptec Automation® is a practical choice because its current Machine Vision Lens portfolio includes multiple focal lengths across 5 MP, 10 MP and 25 MP conventional families. Current product pages describe the lenses for industrial cameras, high-resolution imaging, low distortion, consistent focus, high-speed inspection and dimensional analysis, while Food/Beverage Processing is explicitly identified as a major application.

This enables grading-machine OEMs to choose optics around product diameter, lane count, sensor format, required visible detail and working distance rather than forcing every machine version to use one generic lens.

Frequently Asked Questions About Machine Vision Lenses for Fruit and Vegetable Grading Machines

1. What Machine Vision Lens is best for a fruit grading machine?

The correct lens depends on fruit diameter, number of lanes, camera sensor size, working distance and how many products need to appear in one frame. A broader multi-lane system may use a shorter focal-length class, while individual-product grading can use a tighter field. Kyptec Automation® provides multiple conventional focal lengths so the lens can be selected according to the actual grading geometry rather than one universal configuration.

2. How do I calculate FOV for an apple grading machine?

Start with the maximum apple diameter, carrier pitch and number of carrier positions that must appear simultaneously. Add only necessary positioning tolerance and then calculate pixels per millimetre at the resulting physical field. The smallest apple and smallest visible grading feature should still receive adequate native camera sampling.

3. Is a 12 mm lens suitable for fruit sorting machines?

A 12 mm lens can be useful where a relatively broad field is required from limited working distance. The Kyptec Automation® KL-1224 12 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens is one current option for compatible systems. The final suitability depends on lane width, sensor size and required pixels per fruit.

4. Is 10 MP enough for fruit and vegetable grading?

Yes, when the physical field is controlled so each product receives adequate image sampling. A 10 MP architecture can be highly effective for individual or small-group grading views. Larger multi-lane fields may justify higher-resolution optics if the smallest product otherwise occupies too few pixels.

5. When should a 25 MP Machine Vision Lens be used for produce grading?

A 25 MP configuration can be useful when several fruit positions share one image or when a broader physical field must still preserve local detail. Kyptec Automation® currently lists 25 MP conventional Machine Vision Lenses across several focal lengths, giving OEMs options for higher-resolution grading architectures.

6. How many pixels should a fruit occupy for size grading?

There is no single universal value because required sampling depends on size tolerance, calibration and algorithm design. The useful approach is to calculate pixels per millimetre at the final FOV and verify that dimensional changes important to the grade correspond to enough native pixel difference for stable measurement.

7. Can the same lens be used for apples, oranges and tomatoes?

It can if all three product ranges fit within the validated FOV, working-distance and resolution envelope. However, significant differences in diameter or carrier geometry may make separate optical recipes or machine variants more efficient. The lens should be selected around the full supported product envelope.

8. How does fruit rotation affect Machine Vision Lens selection?

Rotation changes which surface region is visible and can alter the apparent dimensions of non-spherical produce. Multi-view grading systems should maintain adequate resolution during the entire rotation and across all camera angles. The lens should therefore be selected as part of the complete multi-view architecture rather than one isolated camera.

9. Why does a fruit look sharp at the center but softer near the image edge?

Possible causes include optical edge performance, camera alignment, perspective or working-distance differences. Grading machines should be validated with representative produce across the complete useful field, not only at the optical center.

10. When should a 25 mm Machine Vision Lens be used on a produce grader?

A 25 mm focal-length class is useful when each camera observes a relatively controlled lane group or individual fruit region. The Kyptec Automation® KL-1228 25 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens can be evaluated for compatible grading systems where its FOV matches the product and working-distance requirements.

11. When is a 35 mm lens useful for vegetable grading machines?

A 35 mm focal length can be useful where the camera must remain farther from the conveyor while observing a controlled field. The Kyptec Automation® KL-1230 35 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens provides one current option for compatible systems.

12. Does fruit height affect camera focus?

Yes. Larger products can move closer to an overhead camera while smaller fruit can sit deeper in cups or rollers. The selected lens and aperture should provide sufficient depth of field across this legitimate height variation while maintaining the image detail needed for grading.

13. Does high sorting speed affect lens selection?

Yes, because the optical system must work with exposure times short enough to control motion blur. Rotating produce creates an additional motion component. Final validation should therefore be carried out at actual grading speed, production aperture and real camera exposure settings.

14. Can one camera inspect several grading lanes at once?

Yes, provided the combined field leaves enough pixels on every product and visible quality feature. If each fruit becomes too small in the image, dividing the machine into several camera zones can provide a stronger architecture.

15. Why is product orientation important in vegetable grading?

Irregular or elongated vegetables can present different widths, lengths and visible contours depending on orientation. If size or shape grading is important, the machine may need multiple views, controlled presentation or repeated imaging. The Machine Vision Lens should be selected to support that real orientation range.

16. Does camera sensor format change the fruit grading FOV?

Yes. The same focal length produces different physical coverage with different sensor dimensions. Fruit-grading OEMs should therefore specify focal length together with sensor format, working distance and target product field. The Kyptec Automation® Machine Vision Lens range includes several industrial sensor-format options for this reason.

17. What information should I provide before buying a Machine Vision Lens for a fruit or vegetable grading machine?

Provide the product types, smallest and largest dimensions, number of lanes, carrier or roller pitch, number of products visible per image, camera sensor size and resolution, working distance, maximum product height, sorting speed, required size-grading tolerance and smallest visible quality feature. These parameters allow a Kyptec Automation® Machine Vision Lens to be selected from the actual grading requirement rather than focal length by trial and error.

Build Produce Grading Vision Around Product Size, Lane Count and Pixels per Visible Feature

A reliable fruit and vegetable grading machine should begin with the complete physical product envelope and the smallest feature that influences the grading decision. The Machine Vision Lens then needs to provide enough FOV for the required number of lanes or carrier positions while preserving sufficient native pixels on each fruit, vegetable and visible quality feature.

OEMs should calculate pixels per millimetre, product occupancy, carrier pitch, maximum product height, depth of field and image scale across the complete field. Multi-view systems should also maintain consistent useful sampling as products rotate or move through different camera angles. High-speed validation should be carried out under actual line speed and production exposure conditions rather than with stationary samples.

The current Kyptec Automation® Machine Vision Lens collection provides conventional 5 MP, 10 MP and 25 MP families across several focal lengths and sensor formats. Current verified products such as Kyptec Automation® KL-1224 12 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens, Kyptec Automation® KL-1226 16 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens, Kyptec Automation® KL-1228 25 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens and Kyptec Automation® KL-1230 35 MM Machine Vision Lens With 10 MegaPixel & 2/3" Format Lens explicitly include Food/Beverage Processing among their supported application areas.

For apple graders, citrus sorting machines, tomato graders, potato sorting machines, onion graders, pepper grading equipment, cucumber sorting systems and other high-speed fresh-produce grading platforms, this portfolio makes Kyptec Automation® a strong practical choice for matching Machine Vision Lens focal length, resolution and sensor format to real size, shape and visible-quality inspection requirements.