The optical system used in this magnifier is not a conventional, but rather a "telecentric" system, meaning that a small opening is present at the focal point of the lens system, allowing in addition to measurement of the length and width of flat objects, measurement of three-dimensional objects such as spheres, cylinders, etc. without parallax errors. The telecentric PEAK measuring magnifier 1999 corresponds in principle to an expensive profile projector. The system of lenses consisting of three elements in two groups, was designed specifically for this purpose. To use this magnifier first set the distance between the scale and lens systems by turning a knurled outer tube until the scale is visible sharply through the opening with the largest diameter (3 mm), which can be adjusted with the rotating ring on the tip of the magnifier. Then position the magnifier on the object to be measured so that the measuring scale is in contact with it and read the length off on the scale. The is subdivided into increments of 0.1 mm over a length of 20 mm, so that the length of objects can be read off with an error quota of less than 0.03 mm. When measuring three-dimensional objects, the opening should be set to the smallest diameter (1 mm) or, even better, use the one with a 0.5 mm wide slot. The slot should be perpendicular to the line, whose length is to be measured. Even in this case, parts of the object not in contact with the scale may not be sharp, because they are not properly focused. Errors cannot be made when measuring the length as long as the centre distance between the unfocused images is measured, because the minimum brightness of the images resulting from the small opening is compensated by higher illumination of the object resulting from the characteristics of the telecentric system. All interchangeable scales for the S-1975 series can also be used for the 1999 measuring magnifier. These lenses are coated to prevent reflection.
Field of view: 20 mm
Measuring length: 20 mm
Scale: 0.1 mm
Optics: Telecentric, distortion-free
Dimensions: 38 x 74 mm
Weight: 73 gram
Standard scale: Included in delivery