Apparatus and methods for measuring mode spectra for ion-exchanged glass substrates having a steep index region are disclosed. An interfacing fluid is provided between the coupling prism and the glass substrate. The interfacing fluid thickness is selected so that the variation in modal birefringence with fluid thickness is reduced to an acceptable level. The coupling prism can include a prism coating on the coupling surface so that the substrate-prism interface includes the prism coating. The coupling prism can also include stand-off members that serve to define the thickness of the interfacing fluid.

Apparatus and methods for measuring mode spectra for ion-exchanged glass substrates having a steep index region are disclosed. An interfacing fluid is provided between the coupling prism and the glass substrate. The interfacing fluid thickness is selected so that the variation in modal birefringence with fluid thickness is reduced to an acceptable level. The coupling prism can include a prism coating on the coupling surface so that the substrate-prism interface includes the prism coating. The coupling prism can also include stand-off members that serve to define the thickness of the interfacing fluid.

A liquid lens can include two or more liquids enclosed in a chamber. The liquid lens can be configured to reduce the chromatic aberration produced when the meniscus formed at the interface of two of the liquids is tilted. This can be accomplished in a number of ways including selecting the liquids to maximize the refractive index difference and minimize the Abbe number difference.

A liquid lens can include two or more liquids enclosed in a chamber. The liquid lens can be configured to reduce the chromatic aberration produced when the meniscus formed at the interface of two of the liquids is tilted. This can be accomplished in a number of ways including selecting the liquids to maximize the refractive index difference and minimize the Abbe number difference.

The invention relates Tunable prism (1) for optical image stabilization, comprising the components: —A container (2) that comprises a membrane (6) comprising at least a transparent portion, the container (2) further comprising a transparent rigid bottom portion (5) facing the membrane (6), wherein the membrane (6) is connected to the bottom portion (5), and wherein the container (2) encloses a volume (7) that is filled with a transparent fluid (3), —A transparent window (8) arranged on the membrane (6), wherein the membrane (6) comprises a deformable portion (6a) extending around an outer edge (8a) of the window (8), such that the window (8) can be tilted around a first and/or a second axis (201, 202) with respect to the bottom portion (5). The invention further relates to an imaging system (50) comprising the tunable prism (1).

The invention relates Tunable prism (1) for optical image stabilization, comprising the components: —A container (2) that comprises a membrane (6) comprising at least a transparent portion, the container (2) further comprising a transparent rigid bottom portion (5) facing the membrane (6), wherein the membrane (6) is connected to the bottom portion (5), and wherein the container (2) encloses a volume (7) that is filled with a transparent fluid (3), —A transparent window (8) arranged on the membrane (6), wherein the membrane (6) comprises a deformable portion (6a) extending around an outer edge (8a) of the window (8), such that the window (8) can be tilted around a first and/or a second axis (201, 202) with respect to the bottom portion (5). The invention further relates to an imaging system (50) comprising the tunable prism (1).

A zoom camera comprising an optical path folding element (OPFE) for folding the light from a first optical path to a second optical path, a first lens having a first optical axis and a first effective focal length EFL.sub.L1, the first optical axis being along the second optical path, a collimating lens having a second optical axis, and an image sensor located on the second optical path, wherein the collimating lens is movable between at least a first state and a second state, wherein in the first state the collimating lens is positioned in the second optical path between the OPFE and the first lens such that light entering the first lens arrives only from the image side of the collimating lens, and wherein in the second state the collimating lens is positioned outside the first optical path such that light entering the first lens does not arrive from the image side of the collimating lens.

The invention relates to a lens, comprising a container (100) defining a volume (V) which is filled with a transparent liquid (2), wherein the container (10) comprises a transparent and elastically deformable membrane (20) and a rigid member (30), wherein the membrane (20) and the rigid member (30) delimit said volume (V), and a lens shaping element (200) that contacts the membrane (20) and defines an area (21) of said membrane (20), which area (21) has an adjustable curvature for adjusting the focal length of the lens (1). According to the invention, the lens (1) is configured to compensate a thermal expansion of the liquid (2) and/or a change of the refractive index of the liquid (2) due to an increased temperature of the liquid (2) in order to reduce an unwanted thermally induced change of the focal length of the lens (1).

The invention relates to a lens, comprising a container (100) defining a volume (V) which is filled with a transparent liquid (2), wherein the container (10) comprises a transparent and elastically deformable membrane (20) and a rigid member (30), wherein the membrane (20) and the rigid member (30) delimit said volume (V), and a lens shaping element (200) that contacts the membrane (20) and defines an area (21) of said membrane (20), which area (21) has an adjustable curvature for adjusting the focal length of the lens (1). According to the invention, the lens (1) is configured to compensate a thermal expansion of the liquid (2) and/or a change of the refractive index of the liquid (2) due to an increased temperature of the liquid (2) in order to reduce an unwanted thermally induced change of the focal length of the lens (1).

Disclosed is a prism sheet, a prism assembly, and a display device. The prism assembly includes a first prism sheet and a second prism sheet stacked with the first prism sheet. The first prism sheet includes a plurality of first subareas, and each first subarea includes at least one first sub-prism; the second prism sheet includes a plurality of second subareas, and each second subarea includes at least one second sub-prism. An orthographic projection of each first subarea on the second prism sheet corresponds to one of the plurality of second subareas one to one; an extending direction of the at least one first sub-prism in a first subarea is perpendicular to an extending direction of the at least one second sub-prism in a second subarea corresponding to the first subarea.