1. Test object geometry for ultrasound transmission calibration

2. Please watch the test-object board. Can you find which number has the brightest background color?

3. With older instruments it was necessary to adjust the vibration amplitude according to the weight of the test object.

4. The central beam of the ultrasound does not fall upon the surface of the test object (32) at a right angle.

5. The vibrating part of the instrument is usually a cylindrical steel stud with an internal thread for attachment of the test object.

6. Firstly, a classification-tree is constructed based on specification of the test object, and then test cases obtained from the classification-tree are refined by generating a disjunctive normal form.

7. The waves that are backscattered from the test object are evaluated in that an acousto-electric transducer, which is located on a semiconductor crystal, detects the oscillations that are produced in the semiconductor crystal by the backscattered ultrasonic waves.

8. For determining aberrations of an optical imaging system (PL), a test object (12,14) comprising at least one delta test feature (10) is imaged either on an aerial scanning detector (110) or in a resist layer (71), which layer is scanned by a scanning device, for example a SEM.