摘要:
An image-taking lens unit has an image-taking lens system that forms an optical image of an object and an image sensor that receives the optical image in a rectangular image-sensing region and converts the optical image into an electrical signal. The image-taking lens system includes a reflective optical element that bends the optical path. Of the lens elements constituting the image-taking lens system, the most image-side lens element called the last lens element is molded of resin, and is given a non-circular outer shape fulfilling a prescribed condition.
摘要:
An image-taking lens unit has an image-taking lens system that forms an optical image of an object and an image sensor that receives the optical image in a rectangular image-sensing region and converts the optical image into an electrical signal. The image-taking lens system includes a reflective optical element that bends the optical path. Of the lens elements constituting the image-taking lens system, the most image-side lens element called the last lens element is molded of resin, and is given a non-circular outer shape fulfilling a prescribed condition.
摘要:
A zoom lens system is composed of negative, positive, negative, and positive lens groups, of which at least the first to third move during zooming. During zooming from the wide-angle end to the telephoto end, the distance between the first and second lens groups decreases, the distance between the second and third lens groups varies, and the distance between the third and fourth lens groups increases. The conditional formulae 1.0≦|f2/f1|≦1.5 and 2.0≦|f4/f1|≦5.0 are fulfilled (f1, f2, and f4 representing the focal lengths of the first, second, and fourth lens groups).
摘要翻译:变焦透镜系统由负,正,负和正透镜组组成,其中至少在变焦期间第一至第三移动。 在从广角端到望远端的变焦期间,第一和第二透镜组之间的距离减小,第二和第三透镜组之间的距离变化,并且第三和第四透镜组之间的距离增加。 满足条件公式1.0≦̸ | f2 / f1 |≦̸ 1.5和2.0≦̸ | f4 / f1 |≦̸ 5.0(f1,f2和f4表示第一,第二和第四透镜组的焦距) 。
摘要:
A variable magnification optical system having at least a first lens group having a negative optical power, a second lens group having a positive optical power, a third lens group having a negative optical power, and a fourth lens element having a positive optical power, in the optical axis direction in zooming, keeps the third lens element immobile with respect to an image surface while moving at least the second lens group and the fourth lens group, whereby: an interval between the first lens group and the second lens group decreases, an interval between the second lens group and the third lens group increases, and an interval between the third lens group and the fourth lens group decreases. Moreover, the variable magnification optical system moves the third lens group in an in-surface direction vertical to the optical axis direction to thereby correct shake resulting from imaging on the image surface, and fulfills predetermined conditional formula.
摘要:
A variable magnification optical system including at least: a first lens group having a negative optical power, a second lens group having a positive optical power, a third lens group having a negative optical power, and a fourth lens group having a positive optical power moves the second lens group in an—in-surface direction vertical to the optical axis direction in zooming to thereby correct shake resulting from imaging on the image surface.
摘要:
A zoom optical system according to the present invention is provided with, in order from an object side thereof: a first lens group having a negative refractive power; a second lens group having a positive refractive power; a third lens group having a negative refractive power; and a fourth lens group having a positive refractive power. The zoom optical system moves at least the second lens group and the third lens group for zooming operation from a wide-angle end to a telephoto end. The zoom optical system moves the third lens group for a focusing operation. The first lens group is provided with, in order from the object side of the zoom optical system, a meniscus lens having a negative refractive power whose concave surface faces an image side of the zoom optical system, a reflective optical element, and at least one lens.
摘要:
A macro lens and an imaging apparatus include, in the order from an object side to an image side, a first lens group, a second lens group, and a third lens group. Focusing is performed by fixing the first lens group and the third lens group, and by moving the second lens group having a positive refractive power as a whole on the optical axis in focusing from an infinite object to a close distance object. The first lens group has a plane S1 and a plane S2 of curvature radii of a same sign and satisfying a specified condition.
摘要:
The disclosed internal focusing large-aperture medium telephoto lens has as lens groups a positive first lens group, a positive second lens group, and a third lens group, in that order from the object side. When focusing on nearby objects, the first lens group and the third lens group have a fixed position relative to the image surface, and the second lens group displaces toward the object side. The second lens group has only one negative lens, and, in order from the object side, has at least a positive lens, a negative lens, and a positive lens. The following expression is fulfilled: −0.5
摘要:
The guide tube for forming a pneumoperitoneum of the present invention comprising a flexible tube having an inner cavity, has an outer diameter that allows the guide tube to be inserted into a puncture needle, a distal end of the guide tube is closed, the distal end is provided with a tip portion that can be held by holding forceps provided in an endoscope, a proximal end of the guide tube is provided with a connecting portion to an insufflation apparatus, and the guide tube is provided with a side hole region having at least one side hole that can establish communication between the inner cavity of the flexible tube and the outside in a case where the inner cavity is pressurized through insufflation. According to the guide tube for forming a pneumoperitoneum of the present invention, only with single puncture from the body surface into the lumen of a lumen organ, a preliminary pneumoperitoneum can be safely and reliably created without damaging other organs, and, at the same time, the part of the lumen organ wall pierced during formation of the pneumoperitoneum can be used as a route for accessing the peritoneal cavity from the lumen of the lumen organ.
摘要:
A zoom lens includes, in order from an object side thereof: a first lens group having a negative optical power and comprising a reflection optical element; a second lens group having a positive optical power; a third lens group having a negative optical power; a fourth lens group having a positive optical power; and, a fifth lens group. The first lens group and the fourth lens group are positioned at a fixed distance and at least the second lens group, the third lens group and the fifth lens group move along an optical axis, for varying a power of the zoom lens from a wide-angle end to a telephoto end. The zoom lens satisfies a predetermined expression relating to a focal length of the first lens group, and a focal length of the zoom lens at the wide-angle end.