The invention discloses an
electric field measuring device. The
electric field measuring device comprises a bubble generator, an insulation reservoir, an
electrostatic generator, a
hydrogen cylinder, a pressure regulating valve, a camera and an
image processing computer, wherein the bubble generator is composed of a film forming device, a motor driving the film forming device to rotate and a gas
nozzle, and the gas sprayed by the gas
nozzle is sprayed to the film forming device to form bubbles; the insulation reservoir provides bubble liquid for the film forming device, and the bubble liquid is insulated from
metal pieces in the bubble generator and the ground; the
electrostatic generator is connected with the insulation reservoir through a wire,
voltage of the bubble liquid in the insulated reservoir produces
voltage for the
electrostatic generator, and the electrostatic generator has charges; the
hydrogen cylinder and pressure regulating valve are connected with the bubble generator through a gas
pipe, the flow of
hydrogen can be controlled by regulating the pressure regulating valve, the sizes of the bubbles are further controlled,
bubble density and air density are equalized, and the bubble gravity is equal to
buoyancy; the camera is used for shooting movement of the bubbles in an external
electric field; the
image processing computer receives videos shot by the camera, processes the videos into movement trails of the bubbles, and calculates the
field intensity distribution of the external electric field.