enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Adjustable-focus eyeglasses - Wikipedia

    en.wikipedia.org/wiki/Adjustable-focus_eyeglasses

    Adjustable focus lenses, like single-focus lenses, also reduce image-jump and spatial distortion in the field of view associated with traditional multi-focal lenses. Additionally, the ideal near-vision correction can be achieved with precision, because the variable lenses emulate the focusing action of the youthful (non-presbyopic) eye.

  3. Dioptre - Wikipedia

    en.wikipedia.org/wiki/Dioptre

    A dioptre ( British spelling) or diopter ( American spelling ), symbol dpt, is a unit of measurement with dimension of reciprocal length, equivalent to one reciprocal metre, 1 dpt = 1 m−1. It is normally used to express the optical power of a lens or curved mirror, which is a physical quantity equal to the reciprocal of the focal length ...

  4. Porro prism - Wikipedia

    en.wikipedia.org/wiki/Porro_prism

    A double Porro prism system reflects light four times. Porro prisms are most often used in pairs, forming a double Porro prism. A second prism rotated 90° with respect to the first, is placed such that light will traverse both prisms. The net effect of the prism system is a beam parallel to but displaced from its original direction, with the ...

  5. Upside down goggles - Wikipedia

    en.wikipedia.org/wiki/Upside_down_goggles

    Upside down goggles, also known as "invertoscopes" by Russian researchers, [1] are optical instruments that invert the image received by the retinas upside down. They are used to study human visual perception, particularly psychological process of building a visual image in the brain. Objects viewed through such a device appear upside down and ...

  6. Review of systems - Wikipedia

    en.wikipedia.org/wiki/Review_of_systems

    A review of systems (ROS), also called a systems enquiry or systems review, is a technique used by healthcare providers for eliciting a medical history from a patient. It is often structured as a component of an admission note covering the organ systems, with a focus upon the subjective symptoms perceived by the patient (as opposed to the objective signs perceived by the clinician).

  7. Abbe–Koenig prism - Wikipedia

    en.wikipedia.org/wiki/Abbe–Koenig_prism

    An Abbe–Koenig prism is a type of reflecting prism, used to invert an image (rotate it by 180°). They are commonly used in binoculars and some telescopes for this purpose. The prism is named after Ernst Abbe and Albert Koenig . The prism is made from two glass prisms, which are optically cemented together to form a symmetric, shallow Vee ...

  8. Human eye - Wikipedia

    en.wikipedia.org/wiki/Human_eye

    The human eye is an organ of the sensory nervous system that reacts to visible light and allows the use of visual information for various purposes including seeing things, keeping balance, and maintaining circadian rhythm . Arizona Eye Model. "A" is accommodation in diopters. The eye can be considered as a living optical device.

  9. Wedge prism - Wikipedia

    en.wikipedia.org/wiki/Wedge_prism

    Wedge prism. The wedge prism is a prism with a shallow angle between its input and output surfaces. This angle is usually 3 degrees or less. Refraction at the surfaces causes the prism to deflect light by a fixed angle. When viewing a scene through such a prism, objects will appear to be offset by an amount that varies with their distance from ...