K9 Double-Concave Lenses — GLA14 Series
From $20 USD
Request a quoteProduct description
N-BK7 optical glass double-concave lenses have two concave surfaces of equal curvature and negative focal length. They diverge incident beams and are used for beam expansion, projection and increasing the focal length of optical systems, including Galilean beam expanders.
Double-concave lenses are generally preferred when the absolute conjugate ratio (object distance divided by image distance) is close to one. Plano-concave lenses are generally preferred for absolute magnification below 0.2 or above 5.
Available coatings: Uncoated; A coating (350–700nm); B coating (650-1100nm); C coating (1050-1700nm).
Schematic
Dimensions in mm unless otherwise stated.
General specifications
General specifications apply at series level. Signed radius values and surface relations follow the source convention; confirm the model drawing for precision optical design. Material is supplied by the series general specifications; the source model table has no separate material field.
- Material
- N-BK7 optical glass
- Surface irregularity
- λ/4 @632.8nm
- Design wavelength
- 587.6nm
- Surface quality
- 40-20
- Diameter tolerance
- +0.0 / -0.1 mm
- Thickness tolerance
- ±0.1 mm
- Focal length tolerance
- ±1%
- Centration error
- <3 arcmin
- Refractive index
- 1.517
- Abbe number
- v = 64.17
- Clear aperture
- >90% of diameter
- Edge bevel
- 0.2mm×45°
Available specifications
USD unit prices. Shipping, taxes and dispatch timing are confirmed with your quotation. Select models and quantities to build your quote list.
28 models
Choose comparison fields
Compare up to four fields. Expand a model to read every specification.
Dia. = diameter; CT = center thickness; ET = edge thickness; BFL = back focal length. Units remain shown in each heading.
| Details | Quote | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| GLA14-012-025 | 12.7 | -25 | 2.5 | 4.1 | -25.81 | -26.17 | Uncoated | $20 | ||
| GLA14-012-030 | 12.7 | -30 | 3 | 4.3 | -30.97 | -31.41 | Uncoated | $20 | ||
| GLA14-012-050 | 12.7 | -50 | 3.5 | 4.3 | -51.15 | -52.1 | Uncoated | $20 | ||
| GLA14-012-075 | 12.7 | -75 | 3.8 | 4.3 | -74 | -77.5 | Uncoated | $20 | ||
| GLA14-025-050 | 25.4 | -50 | 3 | 6.1 | -50.98 | -52.01 | Uncoated | $22 | ||
| GLA14-025-075 | 25.4 | -75 | 3.5 | 5.6 | -76.15 | -77.86 | Uncoated | $22 | ||
| GLA14-025-100 | 25.4 | -100 | 4 | 5.6 | -101.31 | -103.69 | Uncoated | $22 | ||
| GLA14-012-025-A | 12.7 | -25 | 2.5 | 4.1 | -25.81 | -26.17 | A coating (350–700nm) | $25 | ||
| GLA14-012-030-A | 12.7 | -30 | 3 | 4.3 | -30.97 | -31.41 | A coating (350–700nm) | $25 | ||
| GLA14-012-050-A | 12.7 | -50 | 3.5 | 4.3 | -51.15 | -52.1 | A coating (350–700nm) | $25 | ||
| GLA14-012-075-A | 12.7 | -75 | 3.8 | 4.3 | -74 | -77.5 | A coating (350–700nm) | $25 | ||
| GLA14-025-050-A | 25.4 | -50 | 3 | 6.1 | -50.98 | -52.01 | A coating (350–700nm) | $25 | ||
| GLA14-025-075-A | 25.4 | -75 | 3.5 | 5.6 | -76.15 | -77.86 | A coating (350–700nm) | $25 | ||
| GLA14-025-100-A | 25.4 | -100 | 4 | 5.6 | -101.31 | -103.69 | A coating (350–700nm) | $25 | ||
| GLA14-012-025-B | 12.7 | -25 | 2.5 | 4.1 | -25.81 | -26.17 | B coating (650-1100nm) | $25 | ||
| GLA14-012-030-B | 12.7 | -30 | 3 | 4.3 | -30.97 | -31.41 | B coating (650-1100nm) | $25 | ||
| GLA14-012-050-B | 12.7 | -50 | 3.5 | 4.3 | -51.15 | -52.1 | B coating (650-1100nm) | $25 | ||
| GLA14-012-075-B | 12.7 | -75 | 3.8 | 4.3 | -74 | -77.5 | B coating (650-1100nm) | $25 | ||
| GLA14-025-050-B | 25.4 | -50 | 3 | 6.1 | -50.98 | -52.01 | B coating (650-1100nm) | $33 | ||
| GLA14-025-075-B | 25.4 | -75 | 3.5 | 5.6 | -76.15 | -77.86 | B coating (650-1100nm) | $33 | ||
| GLA14-025-100-B | 25.4 | -100 | 4 | 5.6 | -101.31 | -103.69 | B coating (650-1100nm) | $33 | ||
| GLA14-012-025-C | 12.7 | -25 | 2.5 | 4.1 | -25.81 | -26.17 | C coating (1050-1700nm) | $25 | ||
| GLA14-012-030-C | 12.7 | -30 | 3 | 4.3 | -30.97 | -31.41 | C coating (1050-1700nm) | $25 | ||
| GLA14-012-050-C | 12.7 | -50 | 3.5 | 4.3 | -51.15 | -52.1 | C coating (1050-1700nm) | $25 | ||
| GLA14-012-075-C | 12.7 | -75 | 3.8 | 4.3 | -74 | -77.5 | C coating (1050-1700nm) | $25 | ||
| GLA14-025-050-C | 25.4 | -50 | 3 | 6.1 | -50.98 | -52.01 | C coating (1050-1700nm) | $33 | ||
| GLA14-025-075-C | 25.4 | -75 | 3.5 | 5.6 | -76.15 | -77.86 | C coating (1050-1700nm) | $33 | ||
| GLA14-025-100-C | 25.4 | -100 | 4 | 5.6 | -101.31 | -103.69 | C coating (1050-1700nm) | $33 | ||
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Technical notes
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Illustrations and printable specification summaries are reference information, not manufacturing drawings. Confirm technical suitability and final requirements with your quotation.
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