A new variant of multi ocular stereovision has been developed. The system involves a single camera and two orthogonal planar mirrors. The resulting device is low-cost, compact sensor, particularly suitable for depth determination in robot vision applications. The motivation for the work is the need for a sensor determining spatial coordinates of a robot's tool and the object to be processed. The system inherently poses fewer calibration parameters and provides a higher accuracy in the depth determination than traditional two-camera stereo systems. A prototype of the new device has been built, and test results are presented.