## 3 Results
### Turn-On Time and Response Time  
The effectiveness of the proposed device is greatly dependent on its response time, a key factor that holds significant importance in the context of limiting optical radiation exposure to levels safe for shielded devices. To measure the response time, we used an experimental setup depicted in Figure 1c, with a photodiode and an oscilloscope to evaluate the temporal switching behavior. The measurements were performed for the 6 CHBT NLC doped with 1% SBII _w/w_ and NLC cells of 12 \(\upmu\)m and 30 \(\upmu\)m thickness with integrated foil film polarizers. As a light source, we used a polarized CW laser beam (aligned with the optical axis of the initial polarizer of the NLC power limiter) at a wavelength of \(\lambda\) = 532 nm and a diameter of roughly 2 mm. The dynamic response of the optical system to laser powers of 100 mW and 200 mW is illustrated in Figures 4a and 4b, respectively. These plots depict the decay of the transmitted power, adhering to an exponential model P\({}_{0}\cdot\exp(-\text{kt})+y_{0}\), where P\({}_{0}\) [mW], k [1/ms], and y\({}_{0}\) [mW] are fit coefficients. We identified two critical parameters that characterize the temporal behavior of the proposed device: (1) the turn-on time, defined as the duration until a 10% reduction in transmitted power is observed; (2) the response time, defined as the period until a 90% reduction in transmittance is achieved, denoted as T\({}_{1}\) and T\({}_{2}\), respectively, as shown in Figure 4a. These response times, summarized in Table 1, characterize the capability of the device to quickly mitigate excessive optical radiation and ensure the protection of sensitive components. Figure 4: Transmission characteristics of the analyzed TN cells (6 CHBT doped with 1% by weight Sudan Blue II) showing the turn-on time T\({}_{1}\) and the response time T\({}_{2}\) related to the beam of a \(\lambda\) = 532 nm, a diameter 2 mm, and optical power of **(a)** P = 100 mW; **(b)** P = 200 mW. The blue and orange markers represent the transmitted power values from the moment the analyzed sample was exposed to laser radiation (at normal incidence), recorded for NLC cells of a thickness of 12 \(\upmu\)m (blue crosses) and 30 \(\upmu\)m (orange crosses). Solid lines represent the best-fit exponential curves (fit coefficients y\({}_{0}\) [mW], P\({}_{0}\) [mW], k [1/ms]: **(a)** 12 \(\upmu\)m: y\({}_{0}\) = \(-\)0.12, P\({}_{0}\) = 55.2, k = 0.0056; 30 \(\upmu\)m: y\({}_{0}\) = 0.21, P\({}_{0}\) = 31.7, k = 0.0067; **(b)** 12 \(\upmu\)m: y\({}_{0}\) = 0.95, P\({}_{0}\) = 94.3, k = 0.0082; 30 \(\upmu\)m: y\({}_{0}\) = 0.64, P\({}_{0}\) = 63.5, k = 0.0076); **(c–f)** The images captured by the CCD camera blinded by the P = 200 mW light beam of a \(\uplambda\) = 532 nm, width 2 mm, passing through the NLC optical power limiter. Presented in different timeframes: t\({}_{1}\) \(\approx\) 0 ms, t\({}_{2}\) = 67 ms, t\({}_{3}\) = 200 ms, t\({}_{4}\) = 470 ms. The resolution of the images is 300 \(\times\) 300 pixels; **(g)** Normalized intensities (\(\uplambda\)-cut, in the mid-height of images) plotted from images (**e–f**), orange to dark green solid lines, respectively. The turn-on time of the NLC optical power limiter, regardless of the optical beam power and cell thickness, is typically in the range of tens of milliseconds, while the response time is in the range of hundreds of milliseconds. This may be sufficient for certain applications. Figure 4c-f show the images of the laser beam directed straight onto a CCD camera and illustrate the impact of the NLC optical power limiter positioned in front of the imaging objective at different time points: t\({}_{1}\approx\) 0 ms, t\({}_{2}\) = 67 ms, t\({}_{3}\) = 200 ms, and t\({}_{4}\) = 470 ms, with a constant exposure time. Initially, the central area of the image in Figure 4c is highly overexposed, and as time progresses, with the beam getting more attenuated, the central part of the image darkens completely, as demonstrated in Figure 4d-f.