Experimental apparatus for measuring refractive indexes of liquid and measuring method thereof

The invention relates to an experimental apparatus for measuring refractive indexes of liquid. A luminescent device is arranged at the lower end of a cassette; a diaphragm is arranged on the cassette above the luminescent device; flat transmission glass is arranged on the upper surface of the diaphragm; flat image display glass is arranged on the upper surface of the flat transmission glass; a window is machined on the left side of the cassette, and the window is provided with a shading cover; bouffant shading paper is arranged at the upper end of the cassette; two stand columns are arranged on a base; millesimal position finder with scales is arranged at the upper ends of the two stand columns; a hand wheel is arranged at the end of the millesimal position finder; the hand wheel is connected with a lens cone of which the second lower part passes through the bouffant shading paper to penetrate into the cassette through a rotary translation switching mechanism; and a sealplate is arranged between the lens cone and the bouffant shading paper. A method for measuring the refractive indexes of liquid through the measuring device comprises the steps that: liquid to be measured forms a liquid film between the flat transmission glass and the flat image display glass; visible light passes through a clear aperture and the flat transmission glass, and the liquid film of the liquid to be measured to form a circular dart spot which takes an incidence point as the centre of a circle on a frosted surface of the flat image display glass; and the refractive indexes of the liquid to be measured are calculated.