Adjustable observation window

The invention relates to an adjustable observation window, and belongs to the technical field of equipment. The adjustable observation window comprises a double-layer housing of the observation window, synthetic glass fixed in the double-layer housing, a right-angled prism that can rotate around the axis, and a right-angled prism adjustable support; and the right-angled prism is fixed on the right-angled prism adjustable support, and the right-angled prism adjustable support is arranged on the double-layer housing of the observation window. An operator can observe a front bottom object image in the orthophoria angle of the eyes through the adjustable observation window, the maximal visual scope is 3 times that of an original equipment observation window, and blind observation areas in thebottom of equipment are reduced greatly. The plastic housing not difficulty in perforating can be easily mounted on the original observation window, so that the cost is reduced and power-off time is shortened. The adjustable