10x40 binocular used in astronomical Fully optic design and quality control Fessional optic made OEM service

10x40 binocular as astronomical view

1) Model: YK160022) Magnification: 10X3) Objective Diameter: 40mm4) Field of View(m/1000m): 114

    Field of View(ft/1000yds):342

    Field of View(angel):6

5) Eye Relief: 14.6mm6) Exit Pupil Diameter: 4mm7) Minimum Focus Distance: 5m8) Focus System: Center9) Prism System: BK7, Roof prism10) Eyecups: Fold down11) Coating Type: Fully coated (blue, green or ruby coated)12) Waterproof/Fogproof: No13) Color: Black14) Net Weight: 780g15) Unit Measurement: 170 x 50 x 157mm16) Big eyepiece17) Material: Rubber, plastic, aluminium alloy, glass18) Supplyany OEM service

Accessories:Both inner with a black soft nylon carrybag, a plastic bag, lanyard, instructions and cleaning cloth

Independent focus is an arrangement where the two telescopes are focused independently by adjusting each eyepiece. Binoculars designed for heavy field use, such as military applications, traditionally have used independent focusing.Central focusing is an arrangement which involves rotation of a central focusing wheel to adjust both tubes together. In addition, one of the two eyepieces can be further adjusted to compensate for differences between the viewer's eyes (usually by rotating the eyepiece in its mount). Because the focal change effected by the adjustable eyepiece can be measured in the customary unit of refractive power, the diopter, the adjustable eyepiece itself is often called a "diopter". Once this adjustment has been made for a given viewer, the binoculars can be refocused on an object at a different distance by using the focusing wheel to move both tubes together without eyepiece readjustment.

Application:Can be used in Outdoor sports, traveling, viewing, bird watching, hunting, racing, promotional gifts, or others We have our own factory which could make sure the guaranteed quality, most competitive price, and soonest delivery time.

10x40 binocular used in astronomical