As described above, one or more aspects of the present disclosure provide articles having structural color, and methods of making articles having structural color. The present disclosure provides for articles that exhibit structural colors using one or more optical elements. The optical element(s) is disposed on a substrate (e.g., the surface of the article) and when exposed to visible light, the optical element imparts a structural color to the article, where the structural color (e.g., single color, multicolor such as iridescent) is visible color produced, at least in part, through optical effects (e.g., through scattering, refraction, reflection, interference, and/or diffraction of visible wavelengths of light). Different optical elements can impart the same or different structural colors.

The present disclosure provides for articles that exhibit structural colors. The article includes optical stacks that can be incorporated onto one or more components of an article, for example, when the article is an article of footwear, on an upper or sole of an article of footwear. Upon being subjected to abrasive forces, one or more of the layers of the optical stacks are removed, which can alter the appearance (e.g., structural color and/or non-structural color of areas) of the article. In this way, an article may have a certain appearance originally, but can change (e.g., randomly or intentionally) upon application of abrasive forces (e.g., through use or intentionally).

In a method, it is determined that a detachable lens is mounted on an image capture device in a first orientation. A first image of a controlled scene is captured with the detachable lens mounted in the first orientation. It is determined that the detachable lens is mounted on the image capture device in a second orientation that is rotated approximately 180 degrees from the first orientation. A second image of the controlled scene is captured with the detachable lens in the second orientation. A first image circle center of the first image is determined. A second image circle center of the second image is determined. An average image circle center is determined, based on the first image circle center and the second image circle center. The average image circle center is provided to an image stabilization algorithm when the detachable lens is mounted on the image capture device.

The instant disclosure discloses a reticle retaining system comprising an inner pod and an outer pod. The inner pod is configured to receive a reticle that includes a first identification feature. The inner pod comprises an inner base having a reticle accommodating region generally at a geometric center thereof and surrounded by a periphery region, and an inner cover configured to establish sealing engagement with the inner base. The inner base has a first observable zone defined in the reticle accommodating region correspondingly arranged to allow observation of the first identification feature. The outer pod is configured to receive the inner base. The outer pod comprises an outer base having a second observable zone defined thereon observably aligned to the first observable zone of the inner pod upon receiving the inner pod, and an outer cover configured to engage the outer base and cover the inner pod.

An optical system is provided, including a Galilean magnification device, including an objective lens and an eyepiece lens arranged along an axis. One of the objective lens and the eyepiece lens is a positive lens and the other is a negative lens, thereby defining an image working distance; a reticle device within the Galilean magnification device, including a holographic element, the reticle device being configured to receive light for illuminating the holographic element from off the axis and to direct light from the holographic element on the axis, so that light from the holographic element is set at the image working distance by the eyepiece lens. There is also described a method for recording a holographic reticle for use in a Galilean magnification device.

The imaging unit 500 captures an image using a lens having an effective image circle smaller than the imaging surface of an image sensor. A vignetting amount calculation unit 2212 of a detection unit 221 individually calculates, for four corners, a region size of a vignetting region generated in the captured image acquired by the imaging unit 500, for example. A determination unit 2214 detects a change in the region size calculated at the time of focus abnormality detection processing with respect to the region size calculated at the reference time, and determines that a focus abnormality is detected when the change in the region size exceeds a threshold at any of the four corners. This enables accurate detection of focus abnormality.

In general, techniques are described for a personal protective equipment (PPE) management system (PPEMS) that uses images of optical patterns embodied on articles of personal protective equipment (PPEs) to identify safety conditions that correspond to usage of the PPEs. In one example, an article of personal protective equipment (PPE) includes a first optical pattern embodied on a surface of the article of PPE; a second optical pattern embodied on the surface of the article of PPE, wherein a spatial relation between the first optical pattern and the second optical pattern is indicative of an operational status of the article of PPE.

A gaze tracking system includes a contact lens, a photodetector element, a light conditioning element and electronics. The contact lens includes a fiducial having a position. The photodetector element receives a light signal from the fiducial and provides a photodetector output signal. The light signal provides a light intensity pattern at the photodetector. The optical conditioning element receives the light signal and provides a variation in the light intensity pattern on the photodetector in response to changes in the position of the fiducial. And the electronics process the photodetector output signal to calculate the position of the fiducial. A method includes detecting a light signal from a fiducial included in a contact lens, and tracking the contact lens by analyzing the light signal.

A gaze tracking system includes a contact lens, a photodetector element, a light conditioning element and electronics. The contact lens includes a fiducial having a position. The photodetector element receives a light signal from the fiducial and provides a photodetector output signal. The light signal provides a light intensity pattern at the photodetector. The optical conditioning element receives the light signal and provides a variation in the light intensity pattern on the photodetector in response to changes in the position of the fiducial. And the electronics process the photodetector output signal to calculate the position of the fiducial. A method includes detecting a light signal from a fiducial included in a contact lens, and tracking the contact lens by analyzing the light signal.