The AmScope ZM-4TW3-FOR professional trinocular stereo zoom microscope has a pair of 10x and 25x extreme-widefield high-eyepoint eyepieces, a 0.67x-4.5x zoom objective, two Barlow lenses, and a double-arm boom stand. The microscope has an overall magnification range of 2x-225x. The trinocular viewing head has an interpupillary range of 55 to 75mm, a 45-degree inclination to reduce eye and neck strain, and 360-degree rotation to enable sharing. The vertical trinocular port can be used as a C-Mount or 23mm photo port (camera sold separately). The EW10x22mm and EW25x9mm extreme-widefield high-eyepoint eyepieces combine with the 0.67x-4.5x zoom objective to provide zoom magnification and a longer working distance for inspecting large-scale specimens that require handling or repair. The microscope comes with 0.3x and 2.0x Barlow lenses that can be added to the objective to increase the magnification range. A Barlow lens with a magnification of less than 1.0 reduces magnification and increases the working distance, while a Barlow lens with a magnification greater than 1.0 increases the magnification and reduces the working distance. High-eyepoint eyepieces ease viewing for users who wear glasses, and dioptric adjustment accommodates individual eye-strength differences. A stereo microscope, sometimes called an inspection or dissection microscope, has low magnification and a long working distance that enables users to manipulate the object being inspected.

The fiber-optic ring light has a 150W/21V cool-light halogen light source for observing temperature-sensitive specimens. The ring light provides shadow-free illumination, and a rheostat controls the amount of light emanating from the lamp. The ring light has a 2-1/8" (56mm) inner diameter, a 3-1/8" (80mm) outer diameter, and a 35" (890mm) metal-sheathed light cable. Power and adjustment controls are located on a control box to speed adjustments. The light source has a forced-air cooling system to prevent overheating, and a built-in filter slot can be used to change the light color (filters sold separately). The top-mounted door eases access to the bulb, and automatically turns off the power supply when opened. The light uses a 110V-120V power supply. The microscope has a double-arm boom stand that enables users to position the microscope head on all three axes (X, Y, and Z). The stand has 20" double arms, and a 30" overall length. Bilateral focus eases use for left- and right-handed users. The pillar is 17" and the focus rack has a 3" diameter. The solid cast-steel base is 2 x 8-1/4 x 10-1/4 inches (H x W x D, where H is height, the vertical distance from the lowest to highest point; 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.

United Scope manufactures microscopy equipment and accessories under the brand name AmScope. The company, founded in 1996, is headquartered in Irvine, CA.

What's in the Box?

• AmScope ZM-4TW3-FOR stereo zoom microscope with double-arm boom stand
• EW10x22mm eyepieces, 30mm, one pair
• EW25x9mm eyepieces, 30mm, one pair
• 0.67x-4.5x zoom objective
• 0.3x Barlow lens
• 2.0x Barlow lens
• Fiber-optic ring light (HL250-AR)
• Focus rack
• Eye guards, one pair
• Stage clips, one pair