Where is the unwanted infrared energy typically filtered in an infrared system?

In an infrared system, the unwanted infrared energy is typically filtered out at the optics stage. The optics are responsible for focusing and transmitting infrared radiation to the detector. This stage is crucial because it can use various optical filters or materials designed to allow only the desired wavelengths of infrared radiation to pass through, while blocking or reducing unwanted wavelengths that could create noise or false signals. By filtering out these unwanted signals at the optics stage, the system enhances the quality of the data transmitted to the detector, leading to improved system performance and accuracy in target detection and identification. The effectiveness of this filtering is critical in ensuring that the information presented at the detector stage is as clean and relevant as possible, which ultimately contributes to better operational effectiveness in electronic warfare and other applications.