Tag: range finder

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Japanese

Stereoscopic 2 Meter Base Height Finder, Model 93

Stereoscopic 2 Meter Base Height Finder, Model 93

While primarily designed for use by antiaircraft batteries, a range finder of this type may be used by artillery units for determining horizontal as well as vertical range. The eyepieces are of the focusing type. Interpupillary distances may be set to suit the individual observer by means of a lever located on the right eyepiece. The eyepiece assembly also contains two ray filters.

The instrument consists of three major assemblies which are: the Range Finder Table, the Cradle, and the Tripod assembly. The outer tube is made of seamless steel tubing and has seven openings for adjustments. In addition, there are other openings for the eyepiece assembly, wedge windows, infinity correction lens assemblies, range knob, height of image knob, correction wedge assembly, range drum window, and reticle light windows. The optical bar is made of seamless machined steel and represents better machine work than most Japanese fire control instruments.

SPECIFICATIONS

Power         20 diameters
Field of view 2° 15′
Interpupillary setting 56 mm to 74 mm
Diopter adjustment +2 to -4
Limits of range measuring 400 to 20,000 yds.
Base length 2 meters
Overall length 7 ft., 5 5/8 ins.
Weight 201 lbs.
Cradle
   Overall length 36 ins.
   Distance between trunnions 34 11/16 ins.
   Height 23 ins. (approx.)
   Weight 162 lbs.
Tripod
   Overall height 32 ins.
   Weight 100 lbs.

Japanese: p. 183 (March 1, 1945)

Categories
Japanese

Stereoscopic 2 Meter Base Range Finder Model 97 Type 2

Stereoscopic 2 Meter Base Range Finder Model 97 Type 2

This range finder is believed to be designed for use with seacoast defenses. It is provided with an elbow telescope for tracking purposes and a graphical computer for converting slant range to altitude.

A number of its design features are quite similar to those in the Japanese 2 meter base Height Finder. Similarities are noted in the penta prism mounting, central prism assembly, reticle and eyepiece assemblies, night lighting of scales, and the filter assembly. The instrument is constructed with an outer tube, optical tube, and two tubular diaphragms, all of steel. The outer tube is covered with asbestos treated canvas. The tracking telescope provided with this instrument has a power of 10 diameters and a 5 degree field of view. The body is made of cast aluminum. The tracking telescope is attached to the main instrument by means of a dovetail bracket and is locked in place by a spring latch.

Another accessory, the graphical altitude computor, consists of a pendulum arm inclosed in a circular holder. The pendulum is graduated with a vertical scale in increments of 50 meters from 100 to 1,000 meters, which represents slant range. Angle of site is indicated by a graduated scale on the face of the holder. The cradle has the trunnion bearing arms cast as an integral part of the body. The eyeguard assembly is a copy of the Carl Zeiss design.

SPECIFICATIONS

Power        24
Field of view Undetermined
Diameter of entrance pupil 1.9 ins.
Diameter of exit pupil .08 ins.
Base length 2 meters
Diopter movement +2 to -4 diopters
Measuring limits 500 to 20,000 meters
Inter-trunnion distance 35 1/2 ins.
Overall length 86 ins.
Weight 148 lbs.

Japanese: p. 182 (March 1, 1945)

Categories
Japanese

1 Meter Base Range Finder, Model 94

1 Meter Base Range Finder, Model 94

This instrument is a one-meter base, stereoscopic, horizontal base range finder. Ranges are read directly from the reticles.

The outer tube is made of cast aluminum. The inner tube, made of seamless steel tubing, is supported in the outer tube by means of a gimbal joint. The height of image knob is located on the right end of the instrument; the range correction knob is on the left side. The lighting window of the reticle is above the eyepiece plate. An auxiliary open sight is located above the right eyepiece.

Uniform adjustment of interpupillary distance is obtained by connecting the two eyepieces with steel tape forming a figure 8. Rhomboid prisms keep the optical axes of the eyepieces in alignment with the reticles. The penta prism assemblies are held to circular plates which may be rotated to eliminate tilt of image and place both images at the same height in the field of view.

SPECIFICATIONS

Power         8 diameters
Field of view 5°
Base length 1 meter
Diopter movement + and – 4 diopters
Interpupillary setting 55 to 75 mm
Overall length 43 3/4 ins.
Weight 6 lbs., 13 ozs.
Serial number 1218
Measuring limits 250 to 8,000 yds.

Japanese: p. 181 (March 1, 1945)

Categories
Japanese

75 cm Base Range Finder

75 cm Base Range Finder (Japanese)

This instrument is very similar to the 80 cm base range finder, Keuffel and Esser Model 1918. It also resembles the design of the Barr and Stroud instrument. It is, therefore, assumed that it is used much the same as the American 80 cm base, M1914M1 Range Finder. It is a coincidence type range finder with a split field of view, and is used by light field artillery units.

The ocular prism consists of three optical components cemented together resembling the arrangement in the American 1 meter base range finder, M1916. The eyepiece assembly is of the symmetrical type. The halving plate is a thick piece of optical glass with plano parallel surfaces. The measuring wedge and range scale are a single assembly. The latter is illuminated by the light rays entering through the range scale illuminating window, and reflected by a mirror. The objectives, installed as matched pairs are burnished in their cells. The penta prisms and wedge windows resemble those used in American range finders.

An effort has been made, through a bushing in the center of the buffer assemblies, to desiccate the instrument. It is not believed that the eyepiece assemblies can be sufficiently sealed to make this effective.

The tripod is lightly constructed and has no locking device for the legs. The tripod mount permits the range finder to be locked or rotated in azimuth. There is also a leveling device, but no level vial.

SPECIFICATIONS

Base length       75 cm
Magnification12 power
Range100 to 10,000 yds.
Field of viewVertical 2°—horizontal 3°
Weight of range finder9 lbs.
Weight of carrying case6 lbs.

Japanese: p. 180 (March 1, 1945)

Categories
Japanese

40 cm Base Range Finder

40 cm Base Range Finder - WWII, Japanese

This range finder is a superimposed image vertical base instrument designed for use with machine gun and mortar fire. It consists of two major assemblies: the elbow, and the diaspirometer unit and head. The elbow housing is of seamless aluminum, 4 3/4 inches in length. It contains the eye and field lens, an amici prism, a reticle, a penta prism, and the objective lens. The brass diaspirometer unit contains two wedges with connecting gears that govern the aluminum range drum; the extension tube made of seamless aluminum which maintains the base length of the instrument; and the cast aluminum head which houses a penta prism and a weak correction wedge.

The instrument is used in conjunction with a mount and tripod. Because of the short base length, this range finder is not accurate at distant ranges.

SPECIFICATIONS

Power           4 diameters
Field of view (upper field) 11°
      (lower field) 4°
Base length 40 cm
Measuring limits 30 to 1,500 meters

Japanese: p. 179 (March 1, 1945)