Measuring apparatus and method for measuring a modulation transfer function of an afocal optical system

A measuring apparatus for measuring a modulation transfer function (MTF) of an afocal optical system, the measuring apparatus comprising:

• a receiving device for receiving the afocal optical system in a receiving plane;
• a light-providing device having a broad band light source and a cross shaped test structure illuminated by the broad band light source for providing light for illuminating the afocal optical system in the receiving device from a first side;
• a camera for observing the afocal optical system in the receiving device from a second side opposite the first side for generating a camera image, wherein, in an operational state of the measuring apparatus, the light-providing device, the afocal optical system, and the camera are arranged coaxially on or with measurement axes parallel to
• a measuring axis oriented perpendicularly to the receiving plane;
• at least one further light-providing device having a further broad band light source and a further cross shaped test structure illuminated by the further broad band light source for providing further light for illuminating the afocal optical system in the receiving device from the first side, wherein the light-providing device and the further light-providing device are configured for simultaneously providing light as well as providing further light for illuminating the afocal optical system;
• at least one further camera for observing the afocal optical system in the receiving device from the second side for generating a further camera image;
• wherein, in the operational state, the further light-providing device, the afocal optical system, and the further camera are arranged coaxially on or with measurement axes parallel to an oblique measuring axis oriented obliquely to the measuring axis and/or the receiving plane, wherein the camera and the further camera are configured for simultaneously generating the camera image as well as generating the further camera image;
• and
• a transmission interface for transmitting the camera image and the further camera image to an evaluation unit, which is configured to identify the modulation transfer function (MTF) of the afocal optical system by using at least the camera image and/or the further camera image.