The paper presents the description of the new Virtual Scanning Algorithms (VSA), providing sub-pixel resolution. VSA are the algorithms developed specially for EM-6029B (Fig. 1) and EM-6329 (Fig. 2) die-to-database reticle and photomask inspection systems of "Planar" concern (KBTEM-OMO). For the providing of the effective building in of these algorithms to the inspection system, has being created the special two-levels dynamic model of optical image. The paper presents also the building principles of this model. This model allows, on the one hand, to perform the precise alignment of optical image (collected from the reticle) wit a reference image (generated from the design data), and on the other hand -- to perform the analysis of optical image to get optimum mutual position of the digitization grid of the inspection system and detected defects position. VSA calculate the second level of this model. Both the VSA and the second level of dynamic model of optical image are presented the Virtual Scanning sub-System (VSS). VSS allows to increase the detection capability of automatic reticle inspection system by means of achievement sub-pixel resolution. The paper shows, that during the detection of semi-transparent defects, VSA allow, in particular, to get maximum available amplitude contrast of the CCD-signals on the image model. Accordingly, VSA allow also the inspection system to work without using maximum sensitivity settings with the same detection capability. As a result is the reduction of the risk of false or nuisance defects detection, while keeping maximum sensitivity to printable defects. The VSS design and in-house test results are discussed.