EYEPIECE LENS SYSTEM, VIEW FINDER, IMAGE VIEWING APPARATUS, AND IMAGE PICKUP APPARATUS

• Main Author: SHIRASAKI KEN
• Format: Patent
• Language: English
• Published: 13.05.2013
• Subjects: ACCESSORIES THEREFOR; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USINGWAVES OTHER THAN OPTICAL WAVES; APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FORPROJECTING OR VIEWING THEM; CINEMATOGRAPHY; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; ELECTROGRAPHY; FREQUENCY-CHANGING; HOLOGRAPHY; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICAL LOGIC ELEMENTS; OPTICS; PHOTOGRAPHY; PHYSICS; PICTORIAL COMMUNICATION, e.g. TELEVISION; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

PROBLEM TO BE SOLVED: To provide a compact eyepiece lens system having excellent telecentricity on the image display element side, allowing excellent aberration correction, and having good operability.SOLUTION: An eyepiece lens system that forms an enlarged virtual image of a two dimensional image displayed on an image display element 1 includes, in order from the image display element 1 side to the eye side, a first group having a positive refractive power, a second group having a negative refractive power, a third group having a positive refractive power, and a fourth group having a positive refractive power. The first group is composed of a positive meniscus lens having a concave surface facing the image display element side. The second group is composed of one negative lens or two lenses including a negative lens and a positive lens. The third group is composed of one positive lens. The fourth group is composed of one positive lens or two lenses including a negative lens and a positive lens. The eyepiece lens system is telecentric on the image display element side. The eye relief IR defined as the distance from the lens surface closest to the eye in the fourth group to the eye falls within a range (1), and the focal length f (>0) of the entire system and the distance L from the image display element to the eye satisfies a condition (2).