摘要 |
An optical system includes a radiation source, a radiation-illuminating device, and a radiation-collecting device. The radiation source is configured to generate radiation. The radiation-illuminating device is optically coupled to the radiation source and configured to direct and focus the radiation obliquely with respect to an optical axis thereof onto a sample. The radiation-collecting device is configured to collect back-scattered radiation scattered from the sample and spatially separated from noise radiation. Associated apparatus and method are also described. |