It is known that when measuring microscopic test objects used in the optical microscope, specially manufactured test objects are expensive. We have proposed as a test object using the CD-ROM matrix.

The standard distance between tracks is 1,6 ± 0,1 mm. Precision compliance period exceeding twice the resolution immersion lens with an aperture of 1.3. In Figure 4, but the introduction of the image surface CD-ROM and its Fourier transform, where the system maxima corresponds to the period 1,632 microns.

Such a test object is hundreds of times less prominent and can be widely used in medicine, teaching laboratories, etc.

Patent of Ukraine #100033, 10.07.2015.