As an optotype presenting apparatus of a vision testing system, an apparatus arranged to present an optotype or chart on a color liquid crystal display (LCD) has recently been proposed as well as a conventional apparatus arranged to present an optotype on a screen by projection. Furthermore, an apparatus with the LCD for a binocular balance test has been proposed in which two LCDs placed one before the other and two polarization filters having polarization axes perpendicular to each other. In this apparatus, as with the conventional screen projection type apparatus, two polarization filters whose polarization axes are perpendicular to each other are disposed in front of both eyes of an examinee to present an optotype for right eye and an optotype for left eye to both eyes of the examinee (see U.S. Pat. No. 5,331,358 (JP5-130975 (1993)).
However, such configuration having two LCDs and two polarization filters is complicated and expensive and leads to an increase in apparatus size.