The National Optical & Scientific Instruments Model 156 Compound Microscope is a cost-effective option for educational settings. Although the 156 may be easy on the budget, it most definitely is not light in the features department. This microscope provides students with an effective and enlightening learning experience, while also protecting itself from the daily pitfalls of the classroom.
The 156 has 3 DIN standard objectives: 4x, 10x, and 40xR. These objectives provide 40x, 100x, and 400x magnification, giving students a clear and accurate view of specimens for learning. Everything starts with the 45° inclined monocular viewing tube, however. This tube has a widefield 10x eyepiece with pointer, and it also rotates 360° on the head for sharing by more than student.
Helping students see the specimens clearly would be the built-in 5 watt fluorescent illumination. Brighter, and with a longer life than standard 20 watt tungsten bulbs, fluorescent illumination gives off virtually no base heat. The bulb is also rated at 10,000 hours, and is controlled by the base mounted on/off switch, for years of classroom use.
Other ways in which the 156 protects itself center around the focusing system. Separate low position coarse and fine focusing controls have a slip clutch, which prevents over focusing, and thus damage to the system. The microscope also has a safety rack to prevent damage to slides and the objective lenses. And while the stage moves up and down, tension adjustment eliminates drift. Of course, the 156's cast metal construction also keeps it safe against the dangers of life in the classroom.
- Optical System
- Widefield 10x eyepiece with pointer. Accepts optional #965-160 eyepiece reticle
- 45° inclined monocular viewing head rotates 360° for easy sharing by more than one student
- DIN standard 4x (0.10 N.A.), 10x (0.25 N.A.) and 40xR (0.65 N.A.) objectives are supplied for 40x, 100x and 400x magnification. Model 156-S also includes 100xR (1.25 N.A.) oil immersion lens. All are achromatic, parfocalled, parcentered and color-coded
- 4-hole objective turret, reverse position, ball-bearing mounted for smooth, precise changes in magnification
- Built-in 5-watt fluorescent illumination, delivers greater light and longer life than standard 20-watt tungsten bulb. Virtually no base heat. 10,000 hour rated bulb
- Base mounted on/off switch, heavy-duty 3-wire grounded electrical system and plug
- 0.5A time delay fuse
- Separate low position coarse and fine focusing controls
- Stage moves up or down, eyepiece and body remain fixed
- Slip clutch prevents damage to focusing system
- Tension adjustment eliminates stage drift
- Safety rack stop prevents damage to slides and objective lenses
- Large 135mm x 135mm (5-1/4 in. x 5-1/4 in.) stage, with professional quality, low profile mechanical specimen holder with low-position coaxial x-y controls
- 1.25 N.A. Abbe condenser with spiral focusing mount, iris diaphragm, swing-out filter holder, blue filter supplied
- Rugged cast metal, gray enamel finish
- Height: 15" / 380mm; Net weight: 10 lb / 4.6kg