An apparatus for electrical inspection of an electronic device under test and an electro-optical modulator assembly comprising an electro-optical modulator and a modulator mount

An apparatus for electrical inspection of an electronic device under test is disclosed in which the illuminating light does not pass through the imaging lens before reaching the modulator. The system does not require and does not employ a polarization control component of the conventional voltage imaging optical system to eliminate the light noise. This feature of the described optical system substantially reduces the mass, cost and complexity of the overall inspection apparatus. In addition, the mass, cost and complexity of the non-telecentric lens used in the described system is much lower than that in a conventional inspection system. The system incorporates an inspection head including an electro-optical modulator, a bias voltage source generating a bias voltage pattern applied to the electro-optical modulator, a light source for generating a light pulse for illuminating the electro-optical modulator, a non-telecentric lens and a camera for acquiring image of the illuminated electro-optical modulator.