Optically Variable Devices, Their Application and Use

An optically variable device, the device comprising:

• a control element or layer comprising a magnetic material that is permanently or temporarily magnetic, such that a magnetic field emanates from the material;
• one or more responsive optical element(s);
• the control element or layer and the responsive optical element(s) moveable in the device relative to one another upon application of an external influence upon the device, to change the distance of separation of the control element or layer from the responsive optical element(s), and therefore to change the strength of the magnetic field impinging upon the responsive optical element(s) from the magnetic material of the control element or layer;
• the relative movement and/or the change of the strength of the magnetic field impinging upon the responsive optical element(s), causing a change of perceivable or detectable optical properties of the device.