A metrology frame configured to receive and secure a workpiece in preparation for an interferometric determination of a spatial profile of the workpiece with the use of one or more retroreflectors removably cooperated with the frame in known pre-determined spatial relationship with respect the fiducial features of not only the workpiece but those of the metrology frame itself. The metrology frame is necessarily devoid of a holographic optical element, while the measurement apparatus containing such metrology frame employs a hologram configured to generate at least one alignment optical wavefront that spatially converges on the retroreflector. The hologram is preferably structured as a set of constituent holographic regions (contained in the same, unitary or spatially-complementary housing and/or substrate) that perform different but operationally-complementary functions to facilitate the alignment of the metrology frame with respect to the converging optical wavefront with or without the workpiece in the frame. The optical measurement system employing the metrology frame and the hologram. Methods of optical alignment with use of same.

A retroreflective system is disclosed that includes a retroreflective sheet for retroreflecting light, and a light control film disposed on the retroreflective sheet. For a first wavelength, light incident on the light control film at each of a first and second angles of incidence is retroreflected. For a second wavelength, light incident on the light control film at the first, but not the second, angle of incidence is retroreflected.

A retroreflective system is disclosed that includes a retroreflective sheet for retroreflecting light, and a light control film disposed on the retroreflective sheet. For a first wavelength, light incident on the light control film at each of a first and second angles of incidence is retroreflected. For a second wavelength, light incident on the light control film at the first, but not the second, angle of incidence is retroreflected.

A technique of determining the presence of a species in a sample may include passing light through an optical filter. In an example, the optical filter may include a spatially variant microreplicated layer optically coupled to a wavelength selective filter. The wavelength selective filter may have a light incidence angle-dependent optical band. The spatially variant microreplicated layer may be configured to transmit light to a first optical region of the wavelength selective filter at a first predetermined incidence angle and to a second optical region of the wavelength selective filter at a second predetermined incidence angle.

A technique of determining the presence of a species in a sample may include passing light through an optical filter. In an example, the optical filter may include a spatially variant microreplicated layer optically coupled to a wavelength selective filter. The wavelength selective filter may have a light incidence angle-dependent optical band. The spatially variant microreplicated layer may be configured to transmit light to a first optical region of the wavelength selective filter at a first predetermined incidence angle and to a second optical region of the wavelength selective filter at a second predetermined incidence angle.

An example beacon system includes a housing, a laser module at least partly retained within the housing, and a controller operable to control the laser module.

The present disclosed relates to a decoration element and a method for preparing the decoration element. decoration element has dichroism expressing different colors depending on a viewing direction, and has improved visibility of the dichroism.

The disclosed relates to a decoration element and a method for preparing the decoration element. The decoration element has dichroism expressing different colors depending on a viewing direction, and has improved visibility of the dichroism.

The disclosure provides a detecting composition or layer; a film, a device, a tape and a detecting system having the detecting layer; and methods of use thereof.

The disclosure provides a detecting composition or layer; a film, a device, a tape and a detecting system having the detecting layer; and methods of use thereof.