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During the pulsed laser ablation of metals, as well as other materials, the development of a plasma plume close to the ablated surface leads to the emission of radio frequency energy. In this paper, we describe a process for analysing the received radio frequency power (<i>RFP</i>) for an aluminium (Al) surface ablation process in atmosphere using picosecond laser pulses at a wavelength of 1064 nm. The analysis of the <i>RFP</i> was carried out on two sets of experiments, where two parameters of the laser (repetition rate of laser (<i>RRL</i>) and power of laser (<i>PL</i>)) were varied while other parameters remained constant. In addition to the <i>RFP</i> measurement during the laser processing, the spatter area (SA), which is defined in this paper, and the depth of the ablated hole were measured post-process using a 3D microscope. It was observed that there is a direct relationship between (<i>RFP</i>)² and SA. Accordingly, an appropriate RF calibration was performed, which leads to the definition of a quantity called the RF regulation % (<i>RFR</i>%). By comparing the <i>RFR</i> and <i>PL/RRL</i> variations, to which the laser beam fluence is proportional in these experiments, a diagnostic process (i.e., flowchart) for real-time depth evaluation was proposed and experimentally confirmed. This diagnostic process can indicate if the depth of the laser ablated crater is less than or exceeds a predetermined depth, which in this study was set to 15 µm. It is also demonstrated that the SA variation can be estimated in real-time by analysing the received RF power and, secondly, the depth of ablation can be measured in real time using a combination of information from the received RF power and laser parameters.