Measuring, scientific, optical, monitoring, signaling, security and life-saving apparatus, instruments and modules; apparatus, instruments and modules for measuring and detecting gases, molecules or mixtures thereof, and their respective software (for signal reading and processing); electronic components and modules for electronic outputs of apparatus, instruments and modules for measuring and detecting gases, molecules or mixtures thereof, particularly by using ultraviolet, visible or infrared light; apparatus, instruments and modules for measuring and detecting gases, molecules or mixtures thereof, particulary by using a wavelength tunable laser for detecting and analyzing gases, molecules or mixtures thereof by spectrometry; electronic components (included in this class), particularly ASICs (application-specific integrated circuits); electronic modules for controlling lasers and for facilitating reading and processing of signals from apparatus, instruments and modules for measuring and detecting gases, molecules or mixtures thereof, particularly by using ultraviolet, visible or infrared light and/or for connection with computers and/or reading apparatus