Year/Period |
1940-2017 |
Maker |
BLEEKER |
Country |
The Netherlands |
Signature |
SM 247.1: PLANACHROOM / 8× / BLEEKER ZEIST // MADE IN HOLLAND / NOI [in logo] |
Category |
Other optical equipment |
Subcategory |
Magnifying glasses |
Optical 1 |
Compound |
Size of the instrument (h x w x d) |
3.6 × 2.1 × 1.3 cm |
Donated by |
P.P. de Bruijn, Zeist, the Netherlands |
Inventory number |
SM 247 |
Six foldable pocket loupes, with a magnification of 5×, 8×, 10×, 12× en 16×.
The four metal Bleeker magnifiers are doublets, the Rubin magnifier is a triplet.
| Brand | Bleeker | Bleeker | Bleeker | Nedoptifa | Bleeker | R. Rubin |
| Catalogue number | SM 247.5 | SM 247.1 | SM 247.2 | SM 247.3 | SM 247.4 | SM 247.6 |
| Place | Zeist | Zeist | Zeist | Utrecht | Zeist | Antwerpen |
| Magnification | 5× | 8× | 10× | 12× | 16× | 10× |
| Material | plastic | metal | metal | metal | metal | metal |
| Diameter lens (cm) | 2.2 | 1.6 | 1.4 | 1.1 | 0.9 | 1.7 |
| Focal length (cm) | 5.0 | 3.0 | 2.5 | 2.0 | 1.5 | 2.5 |
| Dimensions: | ||||||
| length (cm) | 4.0 | 3.6 | 3.3 | 3.3 | 2.8 | 3.0 |
| width (cm) | 2.8 | 2.1 | 1.7 | 1.7 | 1.5 | 2.1 |
| depth (cm) | 1.3 | 1.3 | 1.3 | 1.1 | 0.9 | 1.9 |

Polarimeter tubes
1900-1950

Viewer cathetometer
BLEEKER
1950-1960

Porro prism binocular 6×30
BLEEKER
ca. 1953

Universal refractometer after Abbe
BLEEKER
1950-1955