Test apparatus for electro-optical printed circuit boards having optical waveguides, the test apparatus comprising a retainer for accommodating an electro-optical printed circuit board, a beamer, a camera, and a control device, wherein the beamer and the camera are configured to be positioned in such a way that light emitted by the beamer may be fed by means of at least one deflecting element into one or more of the optical waveguides of the electro-optical printed circuit board and may be coupled out into the field of vision of the camera by means of at least one further deflecting element, wherein each of the deflecting elements (6, 7) contains several deflecting mirrors and wherein each optical waveguide of the electro-optical printed circuit board is associated with a deflecting mirror of a first deflecting element and a deflecting mirror of a second deflecting element, and wherein the control device is set up in a first phase - to move a first light bar projected by the beamer step-by-step along a first direction over the first deflecting element and to take in each step an image with the camera, wherein the first light bar extends orthogonally to the first direction; - to pick as a first set of images those images from the images supplied by the camera in which at least one deflecting mirror of the second deflecting element lights up; - to move a second light bar projected by the beamer step-by-step along a second direction over the first deflecting element and to take in each step an image with the camera, wherein the second light bar extends orthogonally to the second direction; - to pick as a second set of images those images from the images supplied by the camera in which at least one deflecting mirror of the second deflecting element lights up, and - to determine from the first set and the second set of images for each of the optical waveguides to be tested the position which a light spot needs to assume in the image generated by the beamer so that the light spot exclusively illuminates the deflecting mirror of the first deflecting element which is associated with the optical waveguide to be tested; and wherein in a second phase the control device is set up for each of the optical waveguides to be tested to project with the beamer based on the position determined in the first phase a light spot onto the deflecting mirror associated with the optical waveguide to be tested, wherein the light spot does not illuminate any deflecting mirror which is associated with an optical waveguide adjacent to the optical waveguide to be tested, to record an image by means of the camera, and to determine a quality of the optical waveguide on the basis of the image. - to move a first light bar projected by the beamer step-by-step along a first direction over the first deflecting element and to take in each step an image with the camera, wherein the first light bar extends orthogonally to the first direction; - to pick as a first set of images those images from the images supplied by the camera in which at least one deflecting mirror of the second deflecting element lights up; - to move a second light bar projected by the beamer step-by-step along a second direction over the first deflecting element and to take in each step an image with the camera, wherein the second light bar extends orthogonally to the second direction; - to pick as a second set of images those images from the images supplied by the camera in which at least one deflecting mirror of the second deflecting element lights up, and - to determine from the first set and the second set of images for each of the optical waveguides to be tested the position which a light spot needs to assume in the image generated by the beamer so that the light spot exclusively illuminates the deflecting mirror of the first deflecting element which is associated with the optical waveguide to be tested;