received in the pivot hole 19 a and that the coiled spring 20 is wound around the pivot pole 19 and attached to the lens assembly 10 so as to provide a biasing force to the lens assembly 10 at position 18 in this non deployed position as seen in fig8 b the lens assembly base 10 is held in situ by the hook 23 which is engageable with the eye 21 to deploy the lens assembly 10 the release mechanism button 24 is operated which acts upon the flexible arm 22 to pull the hook 23 downwards and out of the eye 21 thereby releasing the lens assembly base 10 and causing the coiled spring 20 tension to rotate out of the housed position to a perpendicular user position the rotation of the coiled spring 20 acts on the lens assembly 10 which rotates the lens assembly 10 about the pivot pole 19 this can be seen in fig8 a the hook 23 is in operable configuration with a flexible arm 22 and release mechanism button 24 in fig8 c the reading assembly lens 10 can be seen in the deployed position with the coil spring tension unleashed and holding.