Battery weld marks and tabs: controlling reflections with diffuse light
Laser weld marks on battery cases are faint, the metal is frosted and the tabs are mirror-bright. Side-by-side tests show how a flat dome light turns an unreadable weld into a clean outline, and why the camera hole in a dome matters on a shiny tab.
Control what shiny metal reflects.
- LuzFlat dome, 100 × 100 mm emitting
- Tamaño140 × 140 × 11.5 mm
- Distancia de trabajoClose, under the camera
- ResultWeld outline readable after the change
Drag to rotate · scroll to zoomCamera and CAD lens geometry are published models where available. Light housings use printed dimensions; fixtures, parts, beam shapes and spacing illustrate the inspection principle. This is not an optical simulation or a dimensioned installation drawing.
Evidence you can inspect
The supplied lighting comparisons show a clearer weld outline and a change in the reflected dark aperture on a shiny tab.
The source compares lighting arrangements; it does not report weld strength, penetration or a detection rate.
Surface appearance is evidence for an imaging trial. It cannot establish weld integrity beneath the surface.
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.
Shadowless lightFlat domeFlat dome: Flat dome (LS-2LFX100-C): the weld outline is clear and even.
Round domeSquare, hole sized to the partSquare, hole sized to the part: Square shadowless light with the centre hole sized to the part (made to order): no dark spot.
The challenge
A weld seam on an aluminium case is a low-relief mark on a frosted surface. A plain shadowless light scatters off the frosting and the seam disappears into texture.
The tabs are the opposite problem: polished metal mirrors whatever is above it, including the dark camera hole of a dome light.
How it was solved
Weld marks: the test first used the LS-LFX100 shadowless light, where the frosting hid the surface detail. Changing to the LS-2LFX100-C flat dome, which lights the part evenly from a wide range of angles, strengthened the surface lighting and brought the weld outline out clearly.
Tabs: under the LS-DM120-W dome the tab is evenly lit, but the dome's small centre hole shows as a dark spot reflected in the metal. A square shadowless light with its centre hole sized to the long side of the part removes it; we build that to order.
Why it works
- 1
Broad diffuse illumination changes the reflection pattern on frosted metal. In this comparison, the flat dome makes the weld outline easier to distinguish.
- 2
Only 11.5 mm tall, so it fits between the lens and the part on a crowded line.
- 3
On mirror-like parts, anything above the part is in the picture: size the camera hole or move it off the region you measure.
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
Keep good texture in the trial
Include normal frosting, finish variation and acceptable weld marks.
- 02
Challenge the reflection
Vary tab tilt and check for the camera-hole reflection across the full part.
- 03
Confirm the inspection requirement
Separate visible surface defects from weld-quality checks requiring other methods.
The set-up and the parts
| Weld light | Flat dome (LS-2LFX100-C), white |
|---|---|
| Tab light | Dome (LS-DM120-W) or square shadowless, made to order |
| Cámara | Area scan, mounted straight down through the light |
Flat dome, 100 × 100 mm emitting area, 140 × 140 × 11.5 mm.
$329.00In proposed setup
Dome, 120 mm outside, 30 mm centre hole, 52 mm high.
$359.00Separate test / alternative
5 MP 2/3" monochrome: about 41 µm per pixel across a 100 mm field (100 mm / 2448 px).
$819.00In proposed setup
16 mm macro lens, 0.25x to 0.03x; a 100 mm field on a 2/3" sensor needs about 0.085x.
$319.00In 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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Make the next trial specific.
Tell us the part size, smallest defect or tolerance, available working distance, material and line speed. Include what a good part and a reject look like.
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