MV-CS050-10GM(NPOE)View part & specifications →Browse camera options →Home / Case studies / Comb tooth and gap inspection
Application study · Moulded consumer partsComb teeth in silhouette: inspect repeated narrow gaps
A parallel backlight separates a comb from its background and leaves the spaces between its teeth bright. The real capture shows why the narrowest gaps, rather than the overall part width, should drive the camera trial.
Choose sampling for the smallest gap that must remain open.
- MethodWhite parallel backlight
- EvidenceReal application-lab capture
- SetupSource light identified; imaging kit proposed
- AcceptanceValidate on your own parts
Test stationIncluded light holdersCameraObiettivoIlluminazionePartSoftware inspection region
Drag to rotate · scroll to zoomWalk through this setup 5 guided stops
From component to inspection
Understand each choice.
Choose a stop to frame the part in 3D and see why it belongs in this setup. The component notes and links remain available if 3D cannot load.
Proposed component
MV-CS050-10GM(NPOE)
5 MP monochrome global-shutter camera for a bench contrast trial; confirm sampling, sensitivity and exposure on the actual part.
Proposed component
LS-KF1628M-ML
Proposed 16 mm C-mount macro lens. The illustration uses its printed 0.03x magnification at 546 mm working distance. The proposed camera sensor gives a derived 281.52 × 235.52 mm field. Confirm field, focus and residual distortion on the actual sample; this is not calibrated measurement accuracy. Inspect only a centred 1500 × 1200 px software crop (172.5 × 138 mm) inside the backlight area; the whole sensor field is not illuminated.
Tested component
LS-PHFS180150
White parallel backlight named in the comb example; 180 × 150 mm luminous area, 215 × 165 × 21.5 mm printed housing.
Proposed component
LS-BT-XZ-G-8-6045
800 mm column, 600 × 450 mm breadboard, XZ adjustment, glass tray and two lighting holders as listed. Proposed bench fixture; confirm loads, travel and camera/lens clamps.
Inspect the real capture
Follow the contrast to the part.
Choose sampling for the smallest gap that must remain open.
Camera and available lens CAD are published models. Lens and light envelopes use printed dimensions. The linked station uses its published base size and column height; carriage, brackets, fittings, parts and spacing are illustrative. Confirm load, travel, fasteners and clearances before ordering. Light paths explain the arrangement and do not simulate optical performance. Representative part geometry is illustrative, not reconstructed inspection evidence.
From the demo to your test benchCameraMV-CS050-10GM(NPOE)View part & specifications →Browse camera options → Imaging lens
LS-KF1628M-MLView part & specifications →Browse imaging lens options → Inspection light
LS-PHFS180150View part & specifications →Browse inspection light options → Test station & mounts
LS-BT-XZ-G-8-6045View part & specifications →Browse test station & mounts options →
Build around the parts you can buy.
Explore each component, check its specifications and compare alternatives. The proposed quote includes the linked test station; its catalog listing includes two lighting holders.
MV-CS050-10GM(NPOE)View part & specifications →Browse camera options →LS-KF1628M-MLView part & specifications →Browse imaging lens options →LS-PHFS180150View part & specifications →Browse inspection light options →LS-BT-XZ-G-8-6045View part & specifications →Browse test station & mounts options →Mount the optics with intent
The station is an optical test bench, with its two lighting holders included in the catalog listing. The 3D column and base follow the published height and footprint. Carriages, clamps and part supports are schematic: confirm camera screw pattern, lens support, light fasteners, permissible load and actual travel before ordering.
Configure the mounting station →Complete the electrical system
Select a controller against the exact light voltage, drive mode and power, then confirm camera data/power/I/O cables and a suitable PC. These are not silently added to the proposed optical kit.
Lighting application-lab catalog capture
Evidence you can inspect
Visible in the images
The repeated teeth, gaps and curved comb body are visible in silhouette.
What the source reports
The catalog identifies comb inspection and the white LS-PHFS180150; it does not report gap tolerances or defect-detection percentages.
How to use this evidence
One example of image contrast, without part dimensions, calibrated results or a labelled set of acceptable and defective combs.
What the camera saw
Cropped from the source test sheet; original test annotations are retained. Captures are not generated or enhanced. Drag the comparison slider or use the image buttons.
The challenge
Fine teeth form a repetitive pattern where one missing or partially filled gap can resemble a normal change in pitch.
The tips, roots and curved outer edge need enough sampling across the entire field.
How it was solved
The catalog identifies the white LS-PHFS180150 parallel backlight. Place the comb in front of the illuminated area and inspect the dark teeth and bright gaps.
The proposed camera and macro lens provide a bench starting point. Confirm the smallest tooth and gap in pixels before setting a rule.
The proposed full-sensor field at 0.03x exceeds the light area. Use a centred 1500 × 1200 px software inspection crop (172.5 × 138 mm) within the illuminated region; the 3D viewing volume shows that inspection region. This does not require a camera hardware-ROI mode.
Why it works
- 1
A transmitted-light arrangement reduces the contribution of surface colour and texture to the tooth outline.
- 2
Parallel illumination is useful to evaluate edge stability; neither it nor a sharp-looking image establishes dimensional accuracy by itself.
From image contrast to a production decision
What to validate on your part
A useful sample image is the starting point. These are the checks that turn the concept into a defensible inspection.
- 01
Challenge the narrow gaps
Include flash, incomplete fill and broken teeth close to your acceptance boundary.
- 02
Check every image position
Confirm focus and gap sampling at the two ends as well as the centre.
- 03
Repeat the loading
Vary placement and tilt within the planned fixture limits and record false calls.
Explore your inspection requirementsNo limit from motion
How many pixels cover your feature?
Compare feature coverage, camera pixel requirements and exposure using your own planning inputs. These are calculated planning values, not inspection results or an accuracy specification.
Editable planning scenario. Adjust these example inputs for your application; they are separate from the source test and 3D setup. Motion allowance and target coverage are starting points to validate, not acceptance limits. Pixel count starts from the proposed camera's catalog resolution.
Enter finite numbers in every field. Field width, feature width, target coverage, exposure and allowed motion must be greater than zero; horizontal pixel count must be a positive whole number; material speed may be zero. Use values within the supported numeric range if a calculation cannot be represented.
Object sampling mm/px
Pixels across feature px
Horizontal pixels for target px
Motion during exposure px
Exposure ceiling from motion µs
Formulas and assumptions
The field, feature, speed and exposure start with neutral example values. They are not taken from the source test or the 3D illustration. Allowed motion starts at an editable 0.5-pixel example; it is not a recommended acceptance limit. Target coverage starts at an editable 5-pixel example; it is not a recommended detection or measurement threshold. The horizontal pixel count starts from the catalog Resolution row for MV-CS050-10GM(NPOE). Use the effective width after cropping, binning or decimation if those modes are enabled.
- Object sampling (mm/px) = field width (mm) / horizontal pixels.
- Pixels across feature = feature width (mm) / object sampling (mm/px).
- Horizontal pixels for target = field width (mm) × target pixels across feature / feature width (mm), rounded up to a whole pixel.
- Motion (px) = speed (mm/s) × exposure (µs) / 1,000,000 / object sampling (mm/px).
- Exposure for allowed motion (µs) = allowed motion (px) × object sampling (mm/px) / speed (mm/s) × 1,000,000.
The exposure result is the maximum duration from this motion allowance alone. At zero speed, motion sets no exposure limit; the camera, lighting, saturation and other constraints still apply. A shorter exposure does not itself guarantee a reliable inspection.
Field width and feature width refer to the same object plane. The motion calculation assumes uniform linear motion parallel to the field-width direction and a single exposure. It does not model perspective, vibration, rolling-shutter distortion, diffraction, defocus or optical distortion. A strobe may change the effective exposure.
The target result is a horizontal sampling requirement, not a camera recommendation or a change to the selected camera. It uses the effective image width after cropping, binning or decimation and does not determine the vertical resolution or sensor size. Pixel coverage alone does not establish detectability or measurement accuracy. Validate contrast, lens performance, working distance, illumination, calibration, camera exposure limits and the inspection algorithm on representative parts. Changing field width does not change the 3D model or certify that the proposed lens can achieve that field.
The set-up and the parts
| Illuminazione | White parallel backlight |
|---|---|
| Test light | LS-PHFS180150, white |
| Luminous area (printed) | 180 × 150 mm |
| Camera and lens | Source versions not identified; current proposed parts below |
| 3D spacing | Illustrative, to be confirmed on the sample |
| Derived proposed field | 281.52 × 235.52 mm = sensor dimensions / 0.03x; source field not supplied |
| Illuminated inspection ROI (proposed) | 1500 × 1200 px software crop = 172.5 × 138 mm at 0.03x; full sensor field extends beyond this light, so exclude the unilluminated margins |
| Mounting (proposed) | LS-BT-XZ-G-8-6045; 800 mm column, 600 × 450 mm base, glass tray and two light holders |
IlluminazioneTestedLS-PHFS180150
White parallel backlight named in the comb example; 180 × 150 mm luminous area, 215 × 165 × 21.5 mm printed housing.
$169.00In proposed setupCameraOur pickMV-CS050-10GM(NPOE)
5 MP monochrome global-shutter camera for a bench contrast trial; confirm sampling, sensitivity and exposure on the actual part.
$819.00In proposed setupObiettivoOur pickLS-KF1628M-ML
Proposed 16 mm C-mount macro lens. The illustration uses its printed 0.03x magnification at 546 mm working distance. The proposed camera sensor gives a derived 281.52 × 235.52 mm field. Confirm field, focus and residual distortion on the actual sample; this is not calibrated measurement accuracy. Inspect only a centred 1500 × 1200 px software crop (172.5 × 138 mm) inside the backlight area; the whole sensor field is not illuminated.
$319.00In proposed setupCamera test stationOur pickLS-BT-XZ-G-8-6045
800 mm column, 600 × 450 mm breadboard, XZ adjustment, glass tray and two lighting holders as listed. Proposed bench fixture; confirm loads, travel and camera/lens clamps.
$359.00In proposed setup"Tested" identifies the part named in the source. "Our pick" is a proposed alternative or supporting part. The quote includes only cards marked "In proposed setup", with the quantities shown; other test arrangements are separate. Confirm colour, optics, controllers, power supplies, cables and mounting before ordering.
About this case study: the photos and camera images come from the application laboratory of the maker of the lighting and optics we sell, imaged on the parts shown; your results depend on your part, camera and set-up. This is an application-lab study, not a LumaSpec customer deployment. Source figures are reported results; proposed components require a fresh trial. The 3D scene illustrates the arrangement and does not simulate imaging performance.
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- Campo visivo19.34 × 16.21 mm
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