## 3 Results and Discussion
### The Mechanism of the Formation of the Multiscan Video Signal on the Basis of Its Impulse Response  
One of the most important problems of MODs is their reduction to an ideal device, i.e., the exclusion of the influence of the device circuit from the measurement results. The reconstruction of the real LZ relief using its convolution with impulse response (IR) (i.e., using a VS) is called 'deconvolution'. For such reconstruction, it is necessary to know the parameters of the IR. The problem of deconvolution can be solved by the transformation of the convolution integral [31]:  
\[v(t)=\int\limits_{0}^{\infty}f(x)h(t-x)dx \tag{5}\]  
where _f(x)_ is the initial distribution of the LZ illumination which should be reconstructed; \(h(t-x)\) is the IR that specifies distortions; \(v(t)\) is a VS from the MS. The primary task of the reconstruction of the LZ geometric parameters is the determination of its coordinates in the process of scanning. The MOD is a linear system with constant parameters, and it can be represented in the form of a structural diagram (Figure 5a). In this case, the action \(f(\hat{x})\) is the profile of the LZ (dashed line in Figure 4b), the response \(V(\hat{t})\) is the MOD video signal (solid line), and the MOD work is described by the IR \(h(\hat{t}-\hat{x})\) (where \(\hat{x}=\frac{x_{0}}{\hat{t}}\) is the normalized coordinate of the polling point \(x_{0}\), and \(\hat{t}=\frac{t_{0}}{\hat{t}}\) is the normalized time of polling \(t_{0}\)). The MOD impulse response is the function \(h(\hat{t}-\hat{x})\), which is the system response to an input signal in the form of a unit Dirac delta pulse. For the MOD, such a pulse is an output signal \(V_{C}\) from an infinitely narrow LZ (i.e., a VS from one MS photodiode unit cell). In this case, the VS at the MOD output can be represented in the form of the convolution of an input signal (the light relief on the photosensitive MOD surface) and the system impulse response. To determine the multiscan IR, we wrote the system of equations of currents and voltages for its photodiode unit cell in a scanistor enabling (Figure 6). \[E_{c}=E_{e0}+U_{be}+U_{bc} \tag{6}\]  
\[j_{be}=j_{s}\left(e^{xL_{be}}-1\right)-j_{be}^{f} \tag{7}\]  
\[j_{bc}=-j_{s}\left(e^{xL_{be}}-1\right)+j_{bc}^{f} \tag{8}\]  
Figure 5: The mechanism of the multiscan video-signal formation: (**a**) the scheme of the convolution of the impulse response and light zone parameters; (**b**) the sum video signal \(V\) of the multiscan and the elementary video signals \(V(1)\) of its photodiode cells. \[j_{out}=2j_{bc} \tag{9}\]  
where \(E_{c0}=E_{0}\frac{z_{0}}{T}\) is the potential of the dividing layers \(R^{\prime}_{i}\) and \(R^{\prime\prime}_{i}\) at the polling point \(x_{0}\); \(E_{c}=E_{0}\frac{t_{0}}{T}\)--the value of the sawtooth voltage at the moment of polling \(t_{0}\); \(T\)--period of sawtooth voltage; \(j_{be}\) and \(j_{bc}\)--total currents through base-emitter and base-collector junctions, respectively; \(U_{be}=U_{hel}=U_{be2}\)--base-emitter junction voltage 1, 2; \(U_{bc}\)--base-collector junction voltage; \(j_{s}=j_{be}^{s}=j_{bc}^{s}\)--dark saturation current density of base-emitter and base-collector junctions.