Nikon Optiphot - ER-Tube

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R-4106.A
MECHANISM ANO PRINCIPLE 4. ER-tube (Erect image binooular-tube)
4. ER·tube (Erect image binocular-tuba)
TIUs ER-tube provided with a roof-type depression pnsm, produces erect images.
• Depression angle: 30°
•
Tube magnification: 1 X
• Special beam splitter offers brighter images.
• Owing to Siedentopf type adopted, even though the interpupillary distance is changed between
51 - 75 mm, for which prism cover @is vertically tumed and moved, the tube length keeps
constant ali the times.
e Optical system in the binocular body following the beam splitter prism is constructed the sarne
as for B-tube.
• As shown in Fig. 5, the light rays between §, @ and §.
1
§ are made parallel.
OL
Bcum .~plil prism
Fig. 15
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