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US4881802A Expired / Lapsed US ⏱️ 0.0 years remaining

Combined bright field-dark field incident light illumination apparatus

Assignee: Ernst Leitz Wetzlar GmbH
•
Filing: 1988-05-03
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Granted: 1989-11-21
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Expires: 2008-05-03
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Abstract

Abstract A combined bright field-dark field incident light apparatus 10 for a microscope instrument is described, in which in the dark field illumination the plane of the field diaphragm LF is projected into the object plane 25 via at least one intermediate image LF'. This comprises providing in the beam path at least three annular optical elements (19, 28, 29), arranged so that illuminating rays incident from a skew direction are also projected into the object plane 25. The form of the annular optical elements 19, 27 allows them to be assigned different optical properties at the same time.

Inventors

  • 👤 H. W. Stankewitz

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 08:59
CPC Classifications
G; G02; G02B; G02B21/00; G02B21/06; G02B21/08; G02B21/082; G02B21/084

Claims Analysis

Total Claims: 29
Claim 1
Independent Claim 107 words
A combined bright field-dark field incident light illumination apparatus suitable for microscope instruments having an object plane, comprising: means, including a light source, for producing an illuminating beam including a bright field ray bundle and a generally annular dark field ray bundle, said illuminating beam having a uniformly illuminated area at a point along its axis; means for selectively suppressing the bright field ray bundle; and means for projecting the uniformly illuminated area into the object plane via at least one intermediate image formed in the dark field ray bundle, said projecting means comprising at least three annular optical elements positioned in the dark field ray bundle.
Claim 2
Dependent Claim 107 words
A combined bright field-dark field incident light illumination apparatus suitable for microscope instruments having an object plane, comprising: means, including a light source, for producing an illuminating beam including a bright field ray bundle and a generally annular dark field ray bundle, said illuminating beam having a uniformly illuminated area at a point along its axis; means for selectively suppressing the bright field ray bundle; and means for projecting the uniformly illuminated area into the object plane via at least one intermediate image formed in the dark field ray bundle, said projecting means comprising at least three annular optical elements positioned in the dark field ray bundle.
Claim 3
Independent Claim 18 words
An apparatus as claimed in claim wherein said uniformly illuminated area comprises the plane of a field diaphragm.
Claim 4
Dependent Claim 63 words
An apparatus as claimed in claim 2, wherein: (a) a first annular optical element is located in or near a plane conjugate to an aperture plane; (b) a second annular optical element is located in or near an intermediate image of the field diaphragm; and (c) a third annular optical element is located in or near a plane conjugate to the aperture plane.
Claim 5
Dependent Claim 27 words
An apparatus as claimed in claim 3, wherein the third annular optical element comprises an annular lens having a toric convex area and a toric concave area.
Claim 6
Dependent Claim 20 words
An apparatus as claimed in claim 3, wherein the first optical element additionally comprises at least one centrally located lens.
Claim 7
Dependent Claim 20 words
An apparatus as claimed in claim 5, wherein the first optical element includes an internal recess for accommodating the lens.
Claim 8
Dependent Claim 18 words
An apparatus as claimed in claim 5, wherein the optical element and the lens form a single component.
Claim 9
Dependent Claim 48 words
An apparatus as claimed in claim 3, wherein the first, second and third optical elements are arranged in relation to one another in the illuminating beam so that they project into object plane illuminating beams that are skewed with respect to the optical axis of the illuminating beam.
Claim 10
Dependent Claim 20 words
An apparatus as claimed in claim 3, wherein said third annular optical element has the form of an annular mirror.
Claim 11
Dependent Claim 20 words
An apparatus as claimed in claim 3, wherein said third annular optical element has the form of an annular lens.
Claim 12
Dependent Claim 22 words
An apparatus as claimed in claim 1, wherein at least one of the annular optical elements comprises a curved optically effective area.
Claim 13
Dependent Claim 15 words
An apparatus as claimed in claim 11, wherein the curved optically effective areas are spherical.
Claim 14
Dependent Claim 44 words
An apparatus as claimed in claim 12, wherein each spherically curved area is formed in such a way that its geometric vertex is offset from its center point. plane illuminating beams that are skewed with respect to the optical axis of the illuminating beam.
Claim 15
Dependent Claim 15 words
An apparatus as claimed in claim 11, wherein the curved optically effective areas are aspherical.
Claim 16
Dependent Claim 15 words
An apparatus as claimed in claim 11, wherein the curved optically effective areas are toric.
Claim 17
Dependent Claim 13 words
A microscope comprising an incident light illumination apparatus as defined by claim 1.
Claim 18
Dependent Claim 125 words
A combined bright field-dark field incident light illumination apparatus suitable for microscope instruments having an object plane, comprising: means, including a light source, for producing an illuminating beam including a bright field ray bundle and a generally annular dark field ray bundle, said illuminating beam having a uniformly illuminated area at a point along its axis; means for selectively suppressing the bright field ray bundle; means for projecting the uniformly illuminated area into the object plane via at least one intermediate image, said projecting means comprising at least three annular optical elements positioned in the dark field ray bundle; and wherein a number of the annular optical elements equal to at least one comprises a lens drum having individual curved areas arranged side by side.
Claim 19
Dependent Claim 125 words
A combined bright field-dark field incident light illumination apparatus suitable for microscope instruments having an object plane, comprising: means, including a light source, for producing an illuminating beam including a bright field ray bundle and a generally annular dark field ray bundle, said illuminating beam having a uniformly illuminated area at a point along its axis; means for selectively suppressing the bright field ray bundle; means for projecting the uniformly illuminated area into the object plane via at least one intermediate image, said projecting means comprising at least three annular optical elements positioned in the dark field ray bundle; and wherein a number of the annular optical elements equal to at least one comprises a lens drum having individual curved areas arranged side by side.
Claim 20
Dependent Claim 30 words
An apparatus as claimed in claim 17, wherein the lens drum comprises a first optically effective area comprising a lens drum and a curved or planar second optically effective area.
Claim 21
Dependent Claim 41 words
An apparatus as claimed in claim 17, wherein the number of annular optical elements comprising a lens drum equals two and wherein, the two annular optical elements have the same number of individual curved lens drum area arranged side by side.
Claim 22
Dependent Claim 51 words
An apparatus as claimed in claim 17 wherein, the number of annular optical elements comprising a lens drum equals two and a first annular optical element has a number of lens from areas equal to an even multiple of the number of lens drum areas of a second annular optical element.
Claim 23
Dependent Claim 28 words
An apparatus as claimed in claim 17, wherein the lens drum of the annular optical elements has a combination of spherical and aspherical and/or toric lens drum areas.
Claim 24
Dependent Claim 25 words
An apparatus as claimed in claim 17, wherein individual lenses of the lens drum areas of at least one optical element have different optical densities.
Claim 25
Dependent Claim 26 words
An apparatus as claimed in claim 17, wherein individual lenses of the lens drum areas of at least one optical element have different spectral transmission characteristics.
Claim 26
Dependent Claim 26 words
An apparatus as claimed in claim 17, wherein the lens drum of the annular optical elements has a combination of spherical and toric lens drum areas.
Claim 27
Dependent Claim 26 words
An apparatus as claimed in claim 17, wherein the lens drum of the annular optical elements has a combination of aspherical and toric lens drum areas.
Claim 28
Dependent Claim 117 words
A combined bright field-dark field incident light illumination apparatus suitable for microscope instruments having an object plane, comprising: means, including a light source, for producing an illuminating beam including a bright field ray bundle and a generally annular dark field ray bundle, said illuminating beam having a uniformly illuminated area at a point along its axis; means for selectively suppressing the bright field ray bundle; means for projecting the uniformly illuminated area into the object plane via at least one intermediate image, said projecting means comprising at least three annular optical elements positioned in the dark field ray bundle; and wherein at least two annular optical elements have an identification marker in the form of a protrusion.
Claim 29
Dependent Claim 117 words
A combined bright field-dark field incident light illumination apparatus suitable for microscope instruments having an object plane, comprising: means, including a light source, for producing an illuminating beam including a bright field ray bundle and a generally annular dark field ray bundle, said illuminating beam having a uniformly illuminated area at a point along its axis; means for selectively suppressing the bright field ray bundle; means for projecting the uniformly illuminated area into the object plane via at least one intermediate image, said projecting means comprising at least three annular optical elements positioned in the dark field ray bundle; and wherein at least two annular optical elements have an identification marker in the form of a protrusion.

References Cited (Backward Citations)

DE2021784A1 Cited
US4127318A Cited
DE2925407A1 Cited
DE3100662A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-11-20 1993-05-22 1993-11-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-11-20 1997-05-22 1997-11-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-11-20 2001-05-22 2001-11-21 $7700.00 Window Closed / Lapsed

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