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A solid-phase photosensitizer based on aggregated C60 fullerene and graphene oxide for photodynamic inactivation of pathogens in biological fluids was studied. The most promising technologies of inactivation include the photodynamic effect, which consists in the inactivation of infectious agents by active oxygen forms (including singlet oxygen), formed when light is activated by the photosensitizer introduced into the plasma. Research shows features of solid-phase systems based on graphene and fullerene C60 oxide, which is a combination of an effective inactivating pathogens (for example, influenza viruses) reactive oxygen species formed upon irradiation of the photosensitizer in aqueous and biological fluids, a high photostability fullerene coatings and the possibility of full recovery photosensitizer from the biological environment after the photodynamic action.

A new principle of the projection display based on a laser with the conjugate resonator is offered where one of the mirrors is a spatial light modulator (SLM). Intra-cavity reading of the image created on the SLM provides the oscillation of an optical signal as well a generated image with high luminosity and optical resolution.

In this paper we describe a simple method of small-size images recognition. The method is based on optical expanded encoding of small-size images by using a random phase-only Fourier filter.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The problem of swift steering of laser beams is important for many applications, (projection, marking, engraving, etc.). An approach of intracavity laser beams spatial control was proposed and developed by several teams [1 -9, 14] . Laser beam movement is provided, with thisapproach, by the positioning of the "ruling diaphragm" across the surface of one of mirrors of conjugate laser cavity. The "ruling diaphragm" can be done as a Spatial Light Modulator (SLM). Such modulators are based on various physical effects and can use various modulating media: electrooptical crystals [2, 10], thin semiconductor layers [1 1], ferro-electrical ceramics [12-14], or liquid crystals [6,8]. The electrically-addressed intracavity Spatial Light Modulators (SLMs) were experimentally shown to provide computer-controlled beam addressing to any pixel insidelaserFieldOfView (FOV) [12, 13,14] In the presented article the following aspects are treated of such laser development: (a) design and properties of iniracavity LC SLMs with random addressing to arbitrary pixel in 2D field, and (b) some peculiarities ofDPSSL with intracavity beam scanning, in terms of SLM operation inside the cavity, and thermal lens influence on the laser FOV

Methods of optical design, numerical simulation and experimental testing results are given for the super wide field of vision conjugated optical resonator.

Figure 1 represents schematically the possible sources of pointing faults. First set of faults is connected with optical distortions and misalignements; these faults exist even when the target does not move. Here are: i - atmospherical distortions caused by turbulence, wind, and sometimes by thermal blooming; L2 distortions and misalignements of optical systems (both receiving, affecting the accuracy of target position determination, and transmitting, thus deteriorating output beam quality) ; E3 -faults that are usually connected with a discrete nature of coordinate photoreceptor; E4 -faults and distortions of the laser optical path: dynamic distortions in amplifiers, scanning systems limited accuracy, misalignements and vibrations of the optical elements, etc. It is worth to note that -2' and L4arenonlinearly dependen on the laser beam power. Second set of faults is connected with temporal delays; they are most dangerous when pointing to the moving targets. Here are: T1 - timeof double light pass to target; T2 - time of obtaining signal from photoreceptors; T3 - time of signal processing; T4 - response time of deflectors. So to achieve the high-stable laser beams pointing means to minimize the values of all listed factors. In some cases physical limitations exist (e.g. one can not overcome the diffraction limit for A2; or the light speed limit for T1 , and it easy to see that for long-distance cases this fundamental limitation becomes the strongest) ; in other cases the break-through lies in the development of non-optical technologies (as, say, in computing technology for T3). Thus our efforts were to find some possible and "optical" ways in order to improve the accuracy of laser beams pointing.