Abstract: The present disclosure provides methods, devices, and systems for controlling access to a controlled area. The method may comprise receiving a credential identifier in an access controller associated with an entrance to the enclosed area, and then authenticating the credential identifier. The method may then comprise sending an unlock signal through a solid state relay within the access controller to power a lock associated with but external to the access controller to unlock a door at the entrance to the enclosed area when the credential identifier has been successfully authenticated.

Abstract: A security device includes an array of lenses and a plurality of first and second segments disposed under the array of lenses. At a first viewing angle, the array of lenses presents a first image for viewing without presenting the second image for viewing, and at a second viewing angle different from the first viewing angle, the array of lenses presents for viewing the second image without presenting the first image for viewing. At least one first or second segment can include one or more microstructures or one or more nanostructures configured to produce one or more colors for the first or second image.

Abstract: The present invention provides a spring return device comprising a rotatable drive coupling configured for releasably engaging a rotatable drive part on a first side of the device and configured for releasably engaging a rotatable drive part on an opposite second side of the device. A spring is engaged with the drive coupling, and a retainer retains the spring. The drive coupling is rotatable relative to the retainer, wherein rotation of the drive coupling relative to the retainer in a first direction causes mechanical energy to be stored in the spring.

Abstract: The present invention provides a spring return device comprising a rotatable drive coupling configured for releasably engaging a rotatable drive part on a first side of the device and configured for releasably engaging a rotatable drive part on an opposite second side of the device. A spring is engaged with the drive coupling, and a retainer retains the spring. The drive coupling is rotatable relative to the retainer, wherein rotation of the drive coupling relative to the retainer in a first direction causes mechanical energy to be stored in the spring.