National Optical 215-RLED-ASC Basic Siedentopf Binocular Compound Microscope, WF10x Eyepieces, High-Contrast Objectives, 40x-1000x Magnification, Brightfield, LED Illumination, Abbe Condenser, Iris Diaphragm, Mechanical Stage, 110V-240V or Battery-Powered

The National Optical 215-RLED-ASC Basic Siedentopf Binocular Compound Microscope has a pair of 10x widefield eyepieces, a reverse-mounted nosepiece with four DIN high-contrast objectives that are parcentered and parfocal, LED illumination, nested coarse and fine focus, a 1.25 NA Abbe condenser with iris diaphragm, and a mechanical stage. The Siedentopf binocular head has a pair of eyepieces with interpupillary adjustment, a fixed inclination to reduce eye and neck strain, and rotation capability to provide a more comprehensive view and enable sharing. A Siedentopf binocular head enables the viewer to change the interpupillary distance without changing the tube length, eliminating the need to refocus the image. A reverse-mounted nosepiece keeps objectives out of the way to prevent damage and contamination, and to enable more secure slide handling. ASC (achromatic super contrast) high-contrast objectives provide sharp color distinction. Parcentered and parfocal objectives ensure that the image stays centered and focused when the magnification is changed. The 40xR and 100xR objectives are retractable and spring-loaded to prevent damage to the slide or objective when focusing. The 100xR objective is also an oil objective that provides increased resolution over a standard objective. A basic compound microscope is used in classroom, home school, and hobbyist settings for inspection and dissection of specimens when two-dimensional images are desired.

The microscope has lower (diascopic) brightfield illumination that transmits light up through the specimen for enhanced visibility of translucent and transparent objects. Brightfield (BF) illumination allows the specimen to absorb light, resulting in a dark image on a light background. The LED light source provides bright, cool light for working with temperature-sensitive or live specimens, and a rheostat controls the amount of light emanating from the lamp. The Abbe condenser can be adjusted to control the distance of the light from the stage and has an iris diaphragm to optimize the amount of light illuminating the specimen. The condenser is controlled using a spiral mechanism. The mechanical stage locks the slide into place and provides precise slide manipulation along the X- and Y-axes. Coaxial coarse and fine focus knobs are nested to speed focusing for left-and right-handed viewers, and tension adjustment ensures specimen stays focused during viewing. A slip clutch prevents excess pressure from damaging the slides or objectives, and a stage stop prevents the stage or specimen from coming into contact with the objectives. The cast metal frame provides durability and has a gray enamel finish.

W is width, the horizontal distance from left to right; D is depth, the horizontal distance from front to back.

Microscopes are instruments used to enhance the resolution of an object or image. Types include compound, stereo, or digital. Compound microscopes use a compound optical system with an objective lens and an eyepiece. Stereo microscopes show object depth in a three-dimensional image. Digital microscopes are used to display an image on a monitor, rather than looking through a lens. Microscopes can have monocular (one), binocular (two), or trinocular (three) eyepieces, with varying magnification abilities. Magnification ability refers to the size of an image. Resolution, also known as resolvant power, refers to the clarity of the image. The interaction between field of view (FOV), numerical aperture (NA), and working distance (WD) determines resolution. Microscopes can control magnification through a fixed focus, or through a range of adjustments. They can also utilize LED, fluorescent, and mirror light sources to help control viewing capabilities. Microscopes are widely used in education, lab research, biology, metallurgy, engineering, chemistry, manufacturing, and in the medical, forensic science, and veterinary industries.

National Optical and Scientific Instruments manufactures microscopes and microscope cameras. The company, founded in 1991, is headquartered in Schertz, TX.

What's in the Box?

• National Optical 215-RLED-ASC Basic Siedentopf Binocular Compound Microscope
• (2) WF10x eyepieces with pointer, 18mm
• 4x DIN ASC high-contrast objective
• 10x DIN ASC high-contrast objective
• 40xR (retractable) DIN ASC high-contrast objective
• 100xR (oil, retractable) DIN ASC high-contrast objective
• (3) rechargeable NiMH AA batteries
• Battery charger
• (2) hex key wrenches
• Specimen holder
• Dust cover
• Instructions