Provided herein is an apparatus including a photon emitter array. The photon emitter array includes a number of photon emitters selectively oriented in a number of polarized orientations. The photon emitters are configured to controllably emit photons onto a surface of an article. The apparatus also includes a photon detector positioned to receive photons scattered from features on the surface of the article. The photon detector simultaneously receives photons oriented in the number of polarized orientations. In addition, the photon detector provides information for mapping the features on the surface of the article.

According to one embodiment, a method of evaluating a scratch mark includes, for a magnetic recording medium including a magnetic recording layer containing magnetic particles and a metal oxide grain boundary provided between the magnetic particles, detecting and evaluating a scratch mark based on information about the reflection intensity of light in a predetermined wavelength range. The predetermined wavelength range includes at least a second wavelength range from 600 nm to 700 nm and a first wavelength range from 300 nm to 500 nm.

Provided herein is an apparatus, including at least two photon emitters, each with a preselected polarization orientation, and configured to emit polarized photons onto a surface of an article, and a processing means configured to process photon-detector-array signals corresponding to photons scattered from surface features of the article, and generate one or more surface features maps for the article from the photon-detector-array signals corresponding to the photons scattered from the surface features of the article.

Provided herein are apparatus and methods for inspecting articles for features using interference in light reflected from the articles. The interference may be used to detect, distinguish, and/or map features of articles, which features may include, but are not limited to, surface defects. In at least one embodiment, an apparatus and method includes conveying parallel light along a primary axis through a telecentric lens and a light-splitting device, respectively; illuminating a majority of a surface of an article with the parallel light; conveying reflected light from the surface of the article along the primary axis back through the light-splitting device and the telecentric lens, respectively; and recording interference resulting from a combination of light comprising at least the reflected light from the surface of the article.