# Optimized Passive Defense Measures via IR Imaging
## 1 Introduction
Specifically, ultraviolet radiation falls in a different wavelength intervals of the electromagnetic spectrum, which are shorter than ordinary visible light, but larger than those of \(X\)-rays [17]. Namely, the ultraviolet region covers the wavelengths from the violet edge of visible light, viz. 400 nm to 10 nm, see [10]. Therefore, the UV zone constitutes of about 10% of the total electromagnetic spectrum [3], received as the output of the Sun. Ultraviolet radiation is present in electric arc lamps and mercury vapor lamps, as well. In general, radiation out of the visible portion of the electromagnetic spectrum is harmful [18]. For example, UV light causes sunburn, premature aging, eye damage, skin damage, and other diseases such as skin cancer [18]. Indeed, our study finds applications in a number of common devices such as the infrared sensors, thermal detectors, audible and ultrasonic sensors, railway sensors, and visible light devices such as photo transistors, CdS cells, and others. Hereby, various utilities arise in daily-life, for instance, see Figure 1 for an illustration of the pulsed infrared sensors as a TV remote control [19]. This involves an application of the control theory, infrared sensors, and their pulse generations by a 555-timer or an associated microprocessor. Such sensors are in use over the last 25 years to select channels, adjust the volume and related control systems. Concerning the thermal radiation [2,3], the quantization of the electromagnetic energy forms a spectrum covering the infrared, visible, ultraviolet, and other zones of the light. This is achieved by the thermal agitation of the molecules or atoms of a material. For example, a person in front of a fire can be heated because of the radiation emitted from the fire, even when the surrounding is relatively cold. In this concern, the heat can be transferred from a warmer element to the surrounding by conduction, convection, and radiation [20]. In Sections 3 and 4 the optimization of the radiation distribution is achieved by minimizing the associated energy with respect to the wavelength and surface temperature of the emitting body, see the schematic representation of the absorption in Figure 2.  
Figure 1: A schematic depiction of the pulsed infrared sensors as a TV remote control as in [19]. Here, the pulse generation is realized by a 555-timer or an associated microprocessor. In this paper, we concentrate on the radiation effect of electromagnetic field [21]. Note that the heat transfer (mediated via the above mentioned conduction and convection mechanisms) is effectuated by a definite temperature change over the surface of the material [13; 14; 15]. However, this property may not hold for the case of the heat transfer by radiation. All such phenomena happen because of the existence of the emission spectrum of a radiating body. Emission spectra of arbitrary black bodies can be categorized in various intervals of the wavelength that encompasses all electromagnetic spectrum. As the radiation is absorbed by a black body, it correspondingly radiates heat waves as in the solar light [13]. In this setup, we term the emission of the thermal radiation of a given black body as the black body radiation [14; 15]. Applications of the optimized IR radiation, thermal detectors, and their apt designing techniques fall in the scope of the present research. Instrumentally, thermal detectors can be realized as the devices, which assimilate thermal radiation [11], whereby an increment or decrement in the temperature attributes to a detectable output. The process can fundamentally be viewed as a resulting electrical signal. This is so because there are certain wavelength zones that are physically associated to an undermining energy, which corresponds to a temperature change, rendering an equivalent electrical system [22]. It is worth noticing that there is no wavelength dependency, whereby we find an apt emergence of energy converting instruments as in infrared detectors [23].