Often, assessing a classifying diagnosis in patients with interstitial lung disease provides a diagnostic challenge. Currently HRCT, endoscopic or surgical video assisted thoracoscopic surgery(VATS) assessment including lung biopsies are diagnostic tools for patients with suspected ILD. However, tissue acquisition is associated with morbidity in these patients with an already compromised pulmonary function. In clinical practice this results in the fact that only a minor part of patients with an indication for tissue acquisition are actually undergoing biopsies. The aim of this study is to determine ILD-characteristics on imagign collected with minimal invasive novel optical techniques, to examine whether the addition of novel optical techniques to the diagnostic process of ILD could potentially limit the need for a tissue- (surgical) diagnosis and/or reduce the sampling error rate of biopsies by providing additional information on biopsy location.