Concave Lens Manufacturer,Supplier and Exporter in India
Product Code : EL-SLE-4762
Jlab Export is a leading Concave Lens Manufacturer,and suppliers in India
Concave Lens (code EL-SLE-4762) is a diverging lens with identical concave surfaces on both sides, used to study how a lens that spreads light forms virtual images and how object and image positions are related, in school and college optics practicals. It is listed as Accurate type and offered in focal lengths F/L 5, 10, 15, 20, 25 and 30. It is made by Jain Laboratory Instruments Pvt Ltd (JLab) at its works in Ambala, India.
Specifications
| Parameter | Detail |
|---|---|
| Lens type | Concave (diverging), identical concave surface on both sides |
| Grade | Listed as Accurate type |
| Focal lengths | F/L 5, F/L 10, F/L 15, F/L 20, F/L 25 and F/L 30 — the listing does not state the unit; confirm it when ordering |
| Images formed | Virtual images |
| Teaching use | Object–image relationship of a diverging lens |
| Quality check | Each lens is visually inspected before dispatch |
| Pack quantity | Each (sold individually) |
| Minimum order quantity | 10 units |
| Dispatch time | Usually 7–10 working days |
| Product code | EL-SLE-4762 |
| Manufacturer | Jain Laboratory Instruments Pvt Ltd (JLab) — OEM |
| Country of origin | India (made in Ambala, Haryana) |
How Does It Compare with the JLab Convex Lens?
| Lens | Faces | Effect on parallel light | Image on a screen? |
|---|---|---|---|
| This concave lens (EL-SLE-4762) | Both faces concave, identical | Spreads it out (diverging) | No — virtual images only |
| Convex Lens | Both faces convex, identical | Brings it to a focus (converging) | Yes, when the object is beyond the focus |
Both lenses are listed as Accurate type in the same six focal lengths, so a matched pair of each suits a complete optics bench. Order concave lenses with at least as many convex lenses, because the usual way to measure a concave lens uses a convex one.
What Is a Concave Lens Used For?
A concave lens is thinner at the centre than at the edge and bends parallel light outwards, so the rays appear to come from a focus on the same side as the object. Whatever the object distance, the image is virtual, upright and smaller, which is why a concave lens cannot throw an image onto a screen by itself. Under the sign convention used in school physics its focal length is negative. In class 10 students meet it in the light chapter and again in the human-eye chapter, where concave lenses are the type used in spectacles for short-sightedness. In class 12 practicals its focal length is found with the help of a convex lens: the convex lens forms a real image, the concave lens is placed in the path, and the shift of the image on the optical bench is used to calculate the result.
Handle the lens by its rim, clean it with lens tissue, and keep each focal length in a labelled slot so concave and convex lenses of the same number are not mixed up.
What to Specify When Ordering
- Focal lengths and unit — F/L 5, 10, 15, 20, 25 or 30, with quantities for each.
- Quantity — the minimum order is 10 units.
- Matching convex lenses and holders — add them to the same enquiry for complete bench sets.
Frequently Asked Questions
Is the focal length of a concave lens positive or negative?
Negative, under the sign convention used in school and college physics, because a concave lens diverges light and its focus is virtual. Some older catalogue wording calls it positive; the lens itself is a diverging lens.
Which focal lengths can be ordered?
F/L 5, F/L 10, F/L 15, F/L 20, F/L 25 and F/L 30. The unit is not stated in the listing, so specify the focal length and unit you need.
Why can’t I see a concave lens image on a screen?
Because the image is virtual — the rays only appear to come from it. You view it through the lens, or combine the lens with a convex lens to obtain a real image for measurement.
How do students measure its focal length?
By pairing it with a convex lens on an optical bench: note where the convex lens alone forms an image, insert the concave lens, find the new image position and calculate the focal length from the two positions.
Who manufactures this concave lens?
Jain Laboratory Instruments Pvt Ltd (JLab) makes it at its works in Ambala, Haryana, India, and quotes for it directly as the manufacturer.
OEM Manufacturer
The JLab name belongs to Jain Laboratory Instruments Pvt Ltd, an educational optics and laboratory equipment manufacturer in India, incorporated in 2017 and based on Hargolal Road, Ambala, Haryana. Lenses are made at JLab’s own works rather than bought from traders, so schools, colleges, dealers and importers buy factory-direct, each lens is visually inspected before dispatch, and repeat orders come straight from the manufacturer. JLab exports worldwide and ships to buyers in every region — for example Uganda in East Africa, Peru in South America, Kuwait in the Middle East, Eswatini in Southern Africa and Estonia in Northern Europe. Tender buyers can refer to the JLab lab tenders page.
Optics Bench Companions
- Convex Lens — needed to find the focal length of a concave lens.
- Wooden Lens Holder — holds a convex or concave lens upright on the bench.
- Optical Bench Wooden — keeps the lenses, object and screen in line.
- Lens Cleaning Tissue — for cleaning lenses without scratching them.
- Concave Mirror (Vacuum Type) — a converging mirror for the mirror half of the optics syllabus.
Browse more optics lab equipment in the School Lab Equipment range.
Request a Quote
Quotes come direct from the manufacturer. Use the Add To Cart enquiry button on this page, or send the focal lengths, unit and quantities (minimum 10 units), any convex lenses or holders, and your delivery location through the contact page.
Last updated: 4 October 2026
