Abstract: An optical apparatus uses polarized light to interrogate birefringence properties of the retina to detect the fixation condition of the eye by sensing characteristic birefringence patterns of the retinal structures. Optical components, as well as optional additional components, interfere with the polarization measurements by introducing unwanted retardance which alters the polarization state of the light entering the eye and of the light reaching the detection system. Compensating retarders are provided to nullify the effect of unwanted retardance in the forward and return light paths so the polarization states of the light entering the eye and the light reaching the detection system are not contaminated by the effects of the unwanted retardance. Mueller matrices are used to mathematically calculate the parameters for the compensating retarders for the unwanted retardance. A variable retarder system may also be provided to compensate for the corneal birefringence of the eye via feedback control.

Abstract: The present invention is directed to an indirect ophthalmoscopic system for imaging of the ocular fundus including a headband configured to hold a digital imaging device and a plus eyepiece lens in front of an eye of the examiner, with the plus eyepiece lens positioned in between the digital imaging device and the examiner's eye, such that the examiner is focused upon the display of the digital imaging device. The aperture of the digital imaging device receives light reflected from the ocular fundus of the patient's eye, emanating from the patient's pupil. The examiner examines the patient and composes the image of the ocular fundus directly in the display screen. In this way, what the examiner sees is captured by the digital imaging device. Stereoscopic imagery is obtained by optical means that create side-by-side virtual images of the aperture of the digital imaging device within the pupil of the eye.

Abstract: The present invention is directed to an indirect ophthalmoscopic system for imaging of the ocular fundus including a headband configured to hold a digital imaging device and a plus eyepiece lens in front of an eye of the examiner, with the plus eyepiece lens positioned in between the digital imaging device and the examiner's eye, such that the examiner is focused upon the display of the digital imaging device. The aperture of the digital imaging device receives light reflected from the ocular fundus of the patient's eye, emanating from the patient's pupil. The examiner examines the patient and composes the image of the ocular fundus directly in the display screen. In this way, what the examiner sees is captured by the digital imaging device. Stereoscopic imagery is obtained by optical means that create side-by-side virtual images of the aperture of the digital imaging device within the pupil of the eye.

Abstract: An airbag assembly includes a module with a base plate, an airbag, and a housing for the airbag; and a cover removably attached to the module. The cover can be attached to the housing or base plate without fasteners. An outward extending locking piece is configured to attach to an opening to lock the cover, housing and base plate together. The base plate can also include locking tabs configured to fit in corresponding notches in the cover.