Telescope objective with tunable field of view

We report an electrically controlled telescope objective which can obtain tunable field of view. The proposed telescope objective consists of three main parts: a telescopic objective, a liquid prism and CMOS. The liquid prism is the essential part which composes of two immiscible liquids and makes the system more stable. In particular, there is a transparent partition sheet between liquid–liquid (L–L) interface in the liquid prism which helps to obtain perfect flat interface. When a voltage is applied on the device, the flat interface tilts and field of view (FOV) is deflected. To prove the concept, we fabricate an electrically controlled telescope objective whose tunable FOV is ∼5.8°. The response time is about 480 ms. Application in imaging system to deflect FOV is also demonstrated. The proposed telescope objective has potential applications in surveillance system, unmanned aerial vehicle system, military field and so on.