Fig. 1). Due to the objective lens, the image at this point is turned upside down. However, as the image passes through the prism system, (known as the erective prisms) (2, Fig. 1) it becomes right side up (erect) and changed from right to left, to left to right. After the prisms the image rays pass through the reticle lens (3, Fig. 1) and then through the eyepiece (4, Fig. 1).
3.2 Reticle
Reticle lens (3, Fig. 1) contains vertical and horizontal lines that constitute an M22 reticle. Though reticle scales may form a cross or upside down T (Fig. 2, B) they share the same scale division value: each small division on both vertical and horizontal lines is 5 mils and each big division is 10 mils (360º equals 6400 mils).
Reticle may have an addition scale composed of two lines (B, Fig.2).
Fig. 2
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