Optoelectronic device for detecting the quality of the air in air ducts, the device comprising: • a laser diode (2-1); • a photosensitive resistor (2-2a); • an electronic circuit (2-3) electrically connected to the photosensitive resistor, the electronic circuit being configured to receive the electrical signal (S_dt) and generate therefrom a signal (S_rx_tx) carrying data representative of the measurement of the quantity of particulate; • a wireless signal transceiver (2-4) electrically connected to the electronic circuit (2-3), the transceiver being configured to receive the signal (S_rx_tx) carrying data representative of the measurement of the quantity of particulate and to generate therefrom a wireless signal (S_r) carrying data representative of the measurement of the quantity of particulate present in the portion of the air inside the air duct; the optoelectronic device further comprising a drain (2-11) adapted to receive a portion of the air inside the air duct , wherein the photosensitive resistor (2-2a) is positioned on the bottom of the drain and comprises a photosensitive surface on which the particulate present in the portion of the air deposits by means of the force of gravity, the photosensitive resistor being configured to generate an electrical signal (S_dt) representative of the quantity of particulate deposited on the photosensitive surface; wherein the laser diode is positioned in the proximity of the photosensitive resistor and it is configured to generate an optical beam (F_O) impinging at least partially on the photosensitive surface of the photosensitive resistor, and wherein the electronic circuit comprises a processing unit configured to receive the electrical signal representative of the quantity of particulate deposited on the photosensitive surface and calculate, as a function of the generated electrical signal, a measure of the quantity of particulate deposited per unit of area on the photosensitive surface of the photosensitive resistor. • a laser diode (2-1); • a photosensitive resistor (2-2a); • an electronic circuit (2-3) electrically connected to the photosensitive resistor, the electronic circuit being configured to receive the electrical signal (S_dt) and generate therefrom a signal (S_rx_tx) carrying data representative of the measurement of the quantity of particulate; • a wireless signal transceiver (2-4) electrically connected to the electronic circuit (2-3), the transceiver being configured to receive the signal (S_rx_tx) carrying data representative of the measurement of the quantity of particulate and to generate therefrom a wireless signal (S_r) carrying data representative of the measurement of the quantity of particulate present in the portion of the air inside the air duct; the optoelectronic device further comprising a drain (2-11) adapted to receive a portion of the air inside the air duct , wherein the photosensitive resistor (2-2a) is positioned on the bottom of the drain and comprises a photosensitive surface on which the particulate present in the portion of the air deposits by means of the force of gravity, the photosensitive resistor being configured to generate an electrical signal (S_dt) representative of the quantity of particulate deposited on the photosensitive surface; wherein the laser diode is positioned in the proximity of the photosensitive resistor and it is configured to generate an optical beam (F_O) impinging at least partially on the photosensitive surface of the photosensitive resistor, and wherein the electronic circuit comprises a processing unit configured to receive the electrical signal representative of the quantity of particulate deposited on the photosensitive surface and calculate, as a function of the generated electrical signal, a measure of the quantity of particulate deposited per unit of area on the photosensitive surface of the photosensitive resistor. <EOS>