A device for supporting and suspending objects from a balance point on a surface. The valve body has a supply port to communicate with an external oil feed section, a first drain port to communicate with a first oil pressure chamber, and a second drain port to communicate with a second oil pressure chamber. A light shielding member operative to shield light not contributing to imaging is formed in the neighborhood of a position in the intermediate plane in the erecting equal-magnification lens array plate where an inverted image of the substantially straight light source is formed.