Abstract: A terrestrial telescope with digital camera has an imaging optical system having a group of objective lenses and an imaging element disposed at a position at which an optical image is formed by the group of objective lenses. An observation optical system is provided for observing the optical image transmitted by the group of objective lenses. An optical element is inserted into the optical axis so as to be retractable from the optical axis during imaging. The optical element has a transmission surface having a single-eccentric toroidal configuration with different curvatures in vertical and horizontal planes of the optical element for correcting the position on the imaging element at which the optical image is formed so that the position on the imaging element at which the optical image is formed remains substantially unchanged regardless of whether the optical element is inserted into or retracted from the optical axis of the group of objective lenses.

Abstract: A terrestrial telescope with a digital camera includes an objective lens group and a quick-return half-mirror located on the downstream side of the objective lens group. The quick-return half-mirror can be retractably inserted into the optical axis of the objective lens group. An image pickup device is provided downstream of the quick-return half-mirror, and there is an observation optical system for observing an image reflected by the quick-return half-mirror. The transmission surface of the quick-return half-mirror has a toroidal shape that corrects image-formation positional deviations caused by the insertion of the quick-return half-mirror.

Abstract: A ray of light incident via a pin hole (6) and a field stop (7) having a field of vision a predetermined angle larger than a telescope's actual field of vision that are disposed on an axis (5) in parallel to the optical axis (4) of the telescope is measured in intensity by a photoelectric element (8). When a quantity of light incident on the photoelectric element is larger than a predetermined quantity of light, a shutter (11) is inserted into an optical path of the telescope to cut off a ray of light going into the eyes of the observer. Since an incidence of a quantity of light in excess of a predetermined one into a field of vision a predetermined angle larger than the actual field of vision of the telescope will block the optical path of the telescope, a risk such as damage to the eyes of the observer can be eliminated to prevent an accident even when the observer erroneously observes a strong light-generating object such as the sun.

Abstract: A terrestrial telescope having a digital camera includes an objective lens, an imaging element located at the image-formation plane of the objective lens, and an image processing unit for processing image data captured by the imaging element for record on recording media. A return mirror is disposed between the objective lens and the imaging element to direct the beam to an erecting optical element and an adjustable ocular during observation and direct it to the imaging element during imaging. A reticle is located conjugate to the image-formation plane of the objective lens to indicate the range of the imaging element. A controller controls the return mirror in such a way that it is retracted from the optical path when it is desired to take a picture of an object, and it moves back into the optical path to enable a user to view images of target objects.

Abstract: An apparatus for imaging fluorescent particles comprises an imaging vessel having a lower section defining an interior space for containing fluorescent particles, the lower section having a side wall, a bottom wall and an exterior surface portion defining an entry surface for transmitting into the interior space a flat excitation beam of light. A light projecting device projects a flat excitation beam of light onto the entry surface of the imaging vessel in a direction generally parallel to the bottom wall thereof to illuminate the fluorescent particles. Images of the illuminated fluorescent particles are captured from the bottom wall of the imaging vessel.

Abstract: A vessel for imaging fluorescent particles comprises a tubular body having an upper section, and a lower section defining an interior space for containing fluorescent particles. The lower section of the tubular body has an exterior surface portion forming an entry surface for transmitting into the interior space a beam of light projected in a direction generally parallel to the exterior surface portion of the lower section to illuminate the fluorescent particles.

Abstract: An X-ray imaging apparatus has an image intensifier for converting an X-ray shadowgram of a patient into visible light. A primary lens group collimates the visible light and a secondary lens group forms the image carried by the visible light on a TV imaging device. The primary lens group is provided with a beam splitter for reflecting a part of the light output by the image intensifier toward the secondary lens group and transmitting the remainder thereof to a pick-up optical system for detecting the brightness of the image output by the image intensifier. The exposure of the patient to X-rays can be controlled on the basis of the detected brightness.

Abstract: Disclosed is a laser spot projector for use with a laser coagulation system in which a laser beam is radiated as a focussed spot into a portion selected to be thermally coagulated. A laser source produces a laser beam, and a focussing lens focusses the laser beam on the selected portion in the form of a focussed laser beam spot. A variator lens is displaceably arranged between the laser source and focussing lens for changing the magnification of the laser spot depending upon the displacement of the variator lens. The variator lens is selectably displaceable to two separate positions where the image point is conjugated with the object point with respect to the variator lens. This arrangement makes it possible to selectably provide two focussed laser beam spots each having a different spot diameter.

Abstract: A laser coagulation system adapted for use in an ophthalmological treatment comprises a slit image projector for projecting a slit image into the eyeball of a patient to determine a selected portion of the eyeball to be coagulated, and a laser beam projector for projecting a laser beam onto the selected portion. Both the projectors include a common reflecting means which is divided into two side portions for directing slit light toward the selected portion to be coagulated, and a central portion between the two side portions for directing the laser beam toward the selected portion thereof.

Abstract: An ophthalmological measuring apparatus having a laser-slit projector unit for projecting a laser beam on a portion in a human eyeball, a microscope unit adapted for receiving and observing the light reflected from the portion in the eyeball and a detector unit adapted for displaying the observing point in the eyeball projected by the laser beam.