| EF | ectopic focus; edema factor; ejection fraction; elastic fibril; electric field; elongation factor; e... |
|---|---|
| FA | false aneurysm; Families Anonymous; Fanconi anemia; far advanced; fatty acid; febrile antigen; femor... |
| HPF, hpf | High Power Field; 고배율 시야 |
| LPF, lpf | Low Power Field; 저배율시야 |
| VF | 1) Ventricular Fibrillation ? Tx of Ventricular Fibrillation ... |
| illumination, Kohler | <microscopy> A method of microscopical illumination, first described by A. Kohler, in which an image of the source is focused in the lower focal plane of the condenser and the field diaphragm is focused in the specimen plane. (05 Aug 1998) |
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| illumination, oblique | <microscopy> Illumination from light inclined at an oblique angle to the optical axis. (05 Aug 1998) |
| oblique illumination | Illumination in which a beam of light is directed diagonally to an object so that it is brilliantly illuminated while the surrounding area is in shadow. Synonym: lateral illumination, oblique illumination. Kohler illumination, a method of illumination of microscopic objects in which the image of the light source is focused on the substage condenser diaphragm and the diaphragm of the light source is focused in the same plane with the object to be observed; maximises both the brightness and uniformity of the illuminated field. (05 Mar 2000) |
| erect illumination | An illumination in which the rays of light are directed downward, almost perpendicularly onto the upper surface of the object, which reflects the rays upward into the optical system. Synonym: erect illumination, vertical illumination. (05 Mar 2000) |
| Koehler illumination | <microscopy> Mode of microscope illumination in which the light source is imaged onto the condenser iris diaphragm and the field diaphragm (in front of the lamp collector lens) is imaged by the condenser onto the plane of focus of the specimen. With Koehler illumination, the aperture and field can be regulated independently to provide maximum resolution and optimum contrast. Also, a field with uniform illumination is obtained, circumscribed by the image of the field diaphragm. (05 Aug 1998) |
| Kohler illumination | <technique> The recommended type of optical microscope illumination in which the image of the lamp filament is focussed in the lower focal plane of the substage condenser. As opposed to collimated illumination in which the light emitting surface is imaged in the object. Collimated illumination requires even intensity across the light emitting surface but is preferable for certain types of microscopy. Kohler illumination gives even illumination on the object even if there are irregularities in the brightness of the light emitting surface. (18 Nov 1997) |
| focal illumination | Illumination in which a beam of light is directed diagonally to an object so that it is brilliantly illuminated while the surrounding area is in shadow. Synonym: lateral illumination, oblique illumination. Kohler illumination, a method of illumination of microscopic objects in which the image of the light source is focused on the substage condenser diaphragm and the diaphragm of the light source is focused in the same plane with the object to be observed; maximises both the brightness and uniformity of the illuminated field. (05 Mar 2000) |
| lateral illumination | Illumination in which a beam of light is directed diagonally to an object so that it is brilliantly illuminated while the surrounding area is in shadow. Synonym: lateral illumination, oblique illumination. Kohler illumination, a method of illumination of microscopic objects in which the image of the light source is focused on the substage condenser diaphragm and the diaphragm of the light source is focused in the same plane with the object to be observed; maximises both the brightness and uniformity of the illuminated field. (05 Mar 2000) |
| auditory field | The space included within the limits of hearing of a definite sound, as of a tuning fork. (05 Mar 2000) |
| Broca's field | The posterior part of the inferior frontal gyrus of the left or dominant hemisphere, corresponding approximately to Brodmann's area 44; Broca identified this region as an essential component of the motor mechanisms governing articulated speech. Synonym: Broca's area, Broca's field, motor speech centre. (05 Mar 2000) |
| cardioid dark field condenser | <microscopy> A condenser designed with two reflecting surfaces, the first, a spherical surface which reflects the rays to a second, cardioid (heart-shaped) surface. The virtue in such an arrangement is that, if the cardioid surface is of true figure, the lens is both achromatic and aplanatic. It has a limiting numerical aperture of about 1.0. Thus objectives of a greater numerical aperture cannot be used successfully with it. A true cardioid figure is the trace of a point on the circumference of a circle rolling around an equal, fixed circle. (05 Aug 1998) |
| magnetic field | The sphere of influence of a magnet. (05 Mar 2000) |
| magnetic field gradient | In magnetic resonance imaging, a magnetic field that varies with location, superimposed on the uniform field of the magnet, to alter the resonant frequency of nuclei and allow recovery of their spatial position. Synonym: field gradient. (05 Mar 2000) |
| paraboloid dark field condenser | <microscopy> A lens of parabolic shape. The vertex end is ground back so that its focus can be brought into coincidence with the specimen on the slide. A central stop is provided to block the central rays. It is used chiefly for medium- power work. (05 Aug 1998) |
| receptive field | That part of the retina whose photoreceptors (rods and cones) pertain to a single optic nerve fibre. The response of a neuron to stimulation of its receptive field depends on the type of neuron and the part of the field that is illuminated; an "on-centre" neuron is stimulated by light falling at the centre of its receptive field and inhibited by light falling at the periphery; an "off-centre" neuron reacts in exactly the opposite fashion; that is, it is inhibited by light falling at the centre of its receptive field. In either case, the net response depends on a complex switching action in the retina. When an entire receptive field is equally illuminated, the response of receptors at the centre of the field predominates. (05 Mar 2000) |