Waveguide optics focus elements

A wearable display device, comprising:

• left and right display lens systems configured for augmented reality imaging;
• left and right imaging units of the respective left and right display lens systems configured to generate an augmented reality image;
• and a processor or controller,
• each of the left and right imaging units comprising:
• a waveguide configured for see-through viewing of an environment that is viewable by a user through the waveguide, the waveguide further configured to transmit light of a virtual image that is generated by an image microdisplay to appear as part of the environment;
• and
• two or more focus elements that are:
• integrated within the waveguide such that the environment is viewable by the user through the two or more focus elements;
• and
• each electronically switchable as on to focus the light of the virtual image or off so as not to focus the light of the virtual image, the two or more focus elements being switchable effective to variably focus the light of the virtual image while the light of the virtual image is travelling through the waveguide at a plurality of virtual image focus depths,
• wherein the processor or controller is configured to control the two or more focus elements so that the variable focus of the light of the virtual image approximately correlates to focal distances of the environment perceived by the user.