摘要:
A variable focus (10) lens comprising a fluid chamber (12) containing a first fluid (14) and a second fluid (16) is disclosed. The fluids are non-miscible and in contact over a meniscus (18) and the second fluid is able to alter its shape on the influence of a magnetic field. The second fluid is preferably a ferrofluid. Means (20, 22) for applying a gradient magnetic field (24) over at least a part of the fluid chamber are provided that are capable of inducing a magnetic flux maximizing movement of the fluids, such that the shape of the meniscus varies in dependence on the magnetic field.
摘要:
An optical scanning device provides a radiation source (2,200), a collimator lens (4,40), an objective (7,90) for converting a beam (5,30′) to a scanning spot at the position of an information layer (101) of a record carrier (1,100). The device also includes an electrowetting cell (6). The electrowetting cell (6) acts such that a beam (5,30′) enters the objective (7,90) at a predetermined height of an entrance pupil of the objective (7,90) independent of the position of the objective (7,90) and that the beam (5,30′) forms a predetermined angle at the entrance pupil of the objective (7,90) with the optical axis (8). In this way the rim intensity may be kept constant over the entrance pupil of the objective (7,90).
摘要:
An optical scanning device provides a radiation source 2,200), a collimator lens (4,40), an objective (7,90) for converting a beam (5,30′) to a scanning spot at the position of an information layer (101) of a record carrier (1,100). The device also includes an electrowetting cell (6). The electrowetting cell (6) acts such that a beam (5,30′) enters the objective (7,90) at a predetermined height of an entrance pupil of the objective (7,90) independent of the position of the objective (7,90) and that the beam (5,30′) forms a predetermined angle at the entrance pupil of the objective (7,90) with the optical axis (8). In this way the rim intensity may be kept constant over the entrance pupil of the objective (7,90).
摘要:
A variable reflector device, comprising a reflector (6) arranged to direct light from a light source (7) and a casing (5) containing the reflector (6), a portion of said casing (5) being transparent to light directed by the reflector (6). The reflector (6) is formed by a meniscus (2) at an interface between two immiscible fluids (3,4) contained in said casing (5). According to this design, the spatial distribution of light from the light source is changeable by changing the shape of the meniscus between the two fluids. Since a change in shape of the meniscus is effected by a displacement of fluids rather than of mechanical parts, the change in reflector shape can generally be performed faster and with less energy consumption than is the case with previously known designs. Further, a meniscus between two immiscible fluids can, due to the nature of fluids, take on several different shapes, which is not the case when a solid body reflector is utilised.
摘要:
The electrowetting cel (15) that is primarily to be used as a variable focus lens, comprises a liquid chamber (50) containing a first and a second immiscible fluid (51, 52), which are in contact across a meniscus (14) and of which the first fluid (51) is a polar and the second (52) is electrically conductive. The liquid chamber (50) is provided with an inner face (18), at which a fluid contact layer (10) is present, which has an inherent attraction to the first liquid. An electrode is separated from the liquid chamber (50) through this fluid contact layer (10). The fluid chamber (50) is constructed such that it has a small diameter at an operating point (101) at the inner face (18) than at a point of tangency (102), while a tangent (R1) to the operating point (101) encloses a smaller angle with the optical axis (OA) of the cell (15) than a tangent (R2) to the second point (102). This results in the fact that the meniscus (14) that touches the inner wall (18) at the second point (102) is oriented towards the optical axis and that the cell (15) can have a low construction height.
摘要:
An adjustable mirror includes first and second fluids in contact over a meniscus extending transverse an optical axis. The fluids are substantially immiscible and have different indices of refraction. A reflective surface extends transverse the optical axis. A meniscus adjuster is arranged to controllably alter at least one of the shape and the position of the meniscus.
摘要:
The invention relates to an optical image probe(20) for particularly suited for miniature application e.g. in-vivo. A fluid lens(5) is positioned a housing (19),the fluid lens having a changeable optical power. An image collector (40) is positioned within the housing, the collector being arranged on an optical path of the fluid lens, the collector being displaceable along the said optical path by an actuator (42, 70, 80, 90) in various ways. It is highly advantageous in obtaining a compact optical image probe and which simultaneously has a high zoom factor. Due the possible displacement of the image collector and the changeable optical power of the fluid lens, and cooperation between these two elements, it is possible to obtain a compact endoscope with a wide dynamic range of zoom factor with satisfactory focusing properties.
摘要:
An optical scanning device for scanning optical record carriers having cover layers of different thicknesses. The scanning device has a first mode for scanning a first optical record carrier, a second mode for scanning a second optical record carrier and a third mode for scanning third optical record carrier. The device comprises an objective lens system and a switchable optical element having a first discrete state and a different, second discrete state. The element comprises: a fluid system including a first fluid and a different, second fluid (19); a wavefront modifier (17); and a fluid system switch for acting on the fluid system to switch between the first and second discrete states of the element. When the element is in the first discrete state, the wavefront modifier (17) is substantially covered by the first fluid, and when the element is in the second discrete state, the wavefront modifier (17) is substantially covered by the second fluid (19). The wavefront modifier includes a non-periodic phase structure including a plurality of stepped annular zones separated by steps, the zones forming a non-periodic radial pattern, and is characterized in that the wavefront modifier further includes an aspherical surface. The scanning device is arranged to operate using the element in the second state to generate spherical aberration when in the second mode, the aspherical surface of the element in the second state compensating for more than half of the spherical aberration due to the objective lens system and second record carrier in combination.
摘要:
The present invention provides a discretely adjustable lens (300) that is controllable by means of electrostatic or electrowetting forces. The lens provides two accurately reproducible and freely designable lens states that are defined by interfaces between one out of two fluids (120,121) and at least one lens face (155). Changing place of the fluids by means of electrostatic or electrowetting forces provides for switching between the lens states. The lens may, for example, provide a macro lens option in a camera lens arrangement.
摘要:
An optical element (1) is provided for generating interfacial waves by means of electro wetting. The optical element (1) comprises a fluid chamber (3) with at least one side wall and an optical axis (10). Furthermore the fluid chamber (3) includes a first fluid (A) and a second fluid (B) which are separated by an interface (4), the fluids (A,B) being immiscible. A first electro wetting electrode (2) and a second electro wetting electrode (9) are provided, the first electro wetting electrode (2) is separated from the first fluid (A) and the second fluid (B) by a fluid contact layer (8). The second electro wetting electrode (9) is arranged to act on the first fluid (A). The selected standing or running waves can be formed by providing selected voltages to the first and the second electro wetting electrodes (2,9) respectively.