Quick answer: The LabEquip Optical Concave Lens 50mm is a diverging lens – thinner at the centre than at the edges – used to spread parallel light rays apart and demonstrate virtual image formation. It is a standard ray-optics and optical-bench component for school, college and university physics labs, used for ray tracing, focal-length studies and compound-lens experiments.
Product Description
This lens is thinner at its centre than at its edges. Parallel light rays passing through it diverge on the far side and appear to originate from a virtual principal focus on the incident-light side of the lens, always producing a virtual, upright, diminished image regardless of object distance.
The listed nominal size is 50 mm. The listing does not confirm whether this is the lens diameter, clear aperture or mounting size, and we have not invented a more specific figure – please confirm the exact focal length, optical power, glass composition and surface finish with our sales team before a quantitative experiment. It is intended for secondary-school, college and university physics laboratories for ray tracing, focal-length studies and compound-lens work.
Specifications
| Component type | Concave (diverging) lens |
| Nominal size | 50 mm (exact dimension type not specified for this listing – confirm with our sales team) |
| Image formed | Virtual, upright, diminished (always, regardless of object distance) |
| Typical use | Ray tracing, focal-length studies, compound-lens experiments |
Suggested Procedure
- Inspect the lens for cracks, chips, dust or fingerprints before use.
- Secure it in a compatible holder without applying excessive pressure.
- Align the lens centre with the light source and observation axis.
- Direct a narrow beam or several parallel rays through the lens and trace the diverging emergent rays on a suitable surface.
- Extend the emergent rays backward to locate the virtual principal focus, record your observations, then return the lens to protected storage.
Safety Note
Never look through the lens at the sun, a laser or an intense lamp. Handle the lens only by its edges and do not use it if it is chipped or cracked.
Care & Maintenance
- Remove loose dust with clean air or a soft optical brush.
- Clean the faces using lens tissue and an approved optical cleaner only.
- Store the lens separately in a padded, dry and dust-free container.
- Protect the optical surfaces and edges from impact and abrasion.
Why Choose LabEquip
LabEquip (The Lab Equipment Pvt Ltd) supplies physics, chemistry, biology and STEM laboratory equipment to schools, colleges and training institutes. Pair this lens with our Convex Optical Lens 50mm to compare converging and diverging behaviour, or see our Laser Optics Experiment Tank Kit for a complete ray-optics setup. Visit our homepage to browse the full physics lab equipment range, and ask our sales team to confirm exact focal length and packaging before you order.
Frequently Asked Questions
What does the Optical Concave Lens 50mm demonstrate?
It demonstrates divergence of light through a concave (thinner-at-centre) lens, showing how parallel rays spread apart and appear to come from a virtual focus – always producing a virtual, upright, diminished image.
Does “50mm” mean the lens diameter?
The listing states a nominal 50 mm size, but does not confirm whether this is the overall diameter, clear aperture or a mounting dimension. Please confirm the exact measurement with our sales team.
What is the focal length of this lens?
The focal length is not stated in this listing, so we have not invented a figure. Confirm the exact focal length, glass composition and surface finish with our sales team before a quantitative experiment.
How should I clean and store this lens?
Remove loose dust with clean air or a soft optical brush, clean the faces with lens tissue and an approved optical cleaner only, and store the lens separately in a padded, dry, dust-free container.
Last Updated: September 2026
Reviews
There are no reviews yet.