US Patent 8098142 Vehicle monitoring system

A monitoring device for vehicles includes a housing, at least one electrochromic mirror glass arranged in the housing so as to have a front side facing an observer, and at least one camera. The at least one electrochromic mirror glass comprises a reflective layer that is reflective in the visible spectral range of light. The at least one camera is arranged behind the reflective layer in a viewing direction viewed from the front side. The at least one camera takes images through the reflective layer. The electrochromic mirror glass has an electrochromic layer and the reflective layer is arranged behind the electrochromic layer in the viewing direction.