Abstract: An optical test chart for testing binocular vision. The chart has three lines of text, with the middle line printed or marked in letters or characters which have no polarizing effect. The line above this middle line is marked in letters or characters which have the effect of polarizing light reflected from them, in a plane of polarization in one direction, while the line below the middle line is similarly marked with letters or characters having the effect of polarizing reflected light but with the plane of polarization in a different direction at a substantial angle, preferably a right angle, to the direction of polarization caused by the upper line. The person whose vision is being tested views the test chart through polarizing spectacles, the spectacle in front of one eye having a plane of polarization corresponding to that of the upper line of text on the chart, and the spectacle in front of the other eye having a plane of polarization corresponding to that of the lower line of the text.