US3741716A - Heater for use in the manufacture of plastics filaments - Google Patents
Heater for use in the manufacture of plastics filaments Download PDFInfo
- Publication number
- US3741716A US3741716A US00238846A US3741716DA US3741716A US 3741716 A US3741716 A US 3741716A US 00238846 A US00238846 A US 00238846A US 3741716D A US3741716D A US 3741716DA US 3741716 A US3741716 A US 3741716A
- Authority
- US
- United States
- Prior art keywords
- heater
- internal surface
- filaments
- portions
- spun
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
- D01D5/00—Formation of filaments, threads, or the like
- D01D5/08—Melt spinning methods
- D01D5/084—Heating filaments, threads or the like, leaving the spinnerettes
Definitions
- the present invention relates to a heater for use in the manufacture of macromolecular plastics filaments having a low degree of pre-orientation for the production of high strength threads.
- High strength threads can only be produced when the material spun to make the threads is drawn to a very high degree. A high degree of drawing can only be obtained, however, with material which, when spun, has a low pre-orientation.
- the spinning process has to be carried out in such a manner that the spun filaments should have as low a preorientation as possible.
- a further problem arises in achieving the necessary uniformity, because the filaments can only be drawn to a high degree when, in the spinning process, each of the many capillaries has been uniformly treated. irregularities which may, for example, occur by unsuitable cooling cannot be remedied by further processing and detrimentally affect the quality of the finished thread.
- British Pat. No. 580,832 describes a process and a device for heating freshly spun filaments produced by the dry spinning process.
- the spun filament is drawn off in a direction parallel to the axis of a tube having a vertical axis and heated by means of horizontal radiation.
- the tube is ellitical in cross section and the inner wall of the tube has good reflecting properties.
- the source of heat radiation is situated at one principal focus of the ellipse while the filament is at the other principal focus.
- French Pat. No. 1,347,986 provides a process according to which the freshly spun polyester or polyamide filaments pass through a cylindrical heated tube the gas temperature around the filaments being determined according to the following condition T gas temperature directly on the spinneret in C with 270 C s T 700 C T gas temperature in C at distance L vertically below the spinneret T temperature of spinneret in C D distance from the spinneret in meters V draw-off speed of the spun filaments in m/sec After having left the cylinder the filaments are rapidly cooled by a horizontal air current. Subsequently,
- the invention provides a heater for use in the manufacture of spun plastics filaments which comprises two portions each of which has a truncated right polygonal pyramidal or truncated right conical internal surface that is open ended, the perimeters of the larger ends of the'internal surfaces being congruent and the two portions meeting at their larger ends with the perimeters of the larger ends of the internal surfaces in register with one another, wherein the internal surface of one of the portions is heated and the internal surface of the other portion is thermally reflective.
- each of the said portions is, preferably, a truncated right conical surface.
- FIG. 1 is a perspective view of the heater
- FIG. 2 is an axial cross-section of the heater shown in FIG. 1;
- FIG. 3 illustrates the variation in temperature along the axis of the heater.
- a heater comprises two parts 1 and 2, each of which has the shape of a hollow truncated cone, which are attached to each other at their larger circular openings.
- the lower part 2 is heated while the inside wall of the upper part 1 reflects the heat emitted by the lower part.
- part 1 has the function of a reflector while part 2 has the function of a radiator.
- the lower opening 3 of the heater is protected by an annular screen 4 preventing air blown onto filaments after they have left the heater entering the space below the spinneret and disturbing the course of the capillaries while they are still plastic.
- the diameter d, of the opening in the screen is larger by only 5 to 30 millimeters than the diameter dp of a bundle of capillaries, that is to say,
- the diameter d, of the upper opening of upper part 1 is larger than the diameter of the bundle of capillaries.
- the height L of the radiator is in the range of from 1.0 to 2.5 times the diameter d, of the opening of the upper part. That is to say:
- the cross sectional area of flow should be as large as possible so that the compensation of air can take place at a low speed.
- the largest cross sectional area of the heater should be at least twice the cross sectional area of the bundle of capillaries, that is to say,
- the side line H of the heated part 2 of the heater and the cone angle 4) should be chosen in such a manner that the said perpendicular 5 drawn on the wall of part 2 points to the opposite wall of part I; and arcsin H/2d, l2 arcsin (H/Z s/(d, +d /2 L,) arccot d,+d /2 L
- the biconical shape of the heating radiator allows concentric thermal radiation. The reason why this shape was chosen is that only a minor part of the thermal rays hits the spinneret while the major part is reflected by the conical reflector into the space below the spinneret.
- the reflector I is, therefore, provided with a highly polished surface or coated with a reflecting foil.
- the heating elements of radiator 2 preferably consist of ceramic plates with inserted heating spirals.
- the device according to the invention can be used in melt spinning, preferably spinning of high molecular weight polyesters, more preferably polyethylene terephthalate, and copolyesters, the acid components of which preponderantly consist of terephthalic acid.
- spun filaments of a very low degree of pre-orientation can be obtained, which permit the production of high strength threads. It is likewise possible to increase the throughput of molten polyester since the higher pre-orientation resulting from a higher draw-off speed of the spun filaments can be compensated for in the heater.
- the device according to the invention is also suitable for the continuous spin drawing of filaments from highly viscous material.
- the short biconical heating radiator With the aid of the short biconical heating radiator according to the invention a narrow temperature variation with respect to time and space as indicated in FIG. 3 can be obtained below the spinneret in the solidification zone of the filaments, whereby the solidification is very favourably influenced.
- the temperature is within the indicated limits ll0- 1.7 X 10 l BIL-0.4 T T,, 2 X10 (D/L 0.5)
- the spun filaments produced in this manner have a double refraction DR of (1.6 2.0). 10', measured according to the compensation method of Ehringhous with quartz or calcite compensators. The DR value is calcu-' lated from the ratio of the path difference and the capillary diameter.
- the filaments had a very good uniformity over their length.
- U the average linear deviation of the titer T from the means titer value T:
- the titer T is measured as a function of the filament length l.
- L is the total filament length measured.
- the mean titer value is With the use of the heating radiator according to the invention filaments were produced having a titer nonuniformity U of 0.8%. The spun filaments did not stick together.
- the spun filaments obtained in this manner could be drawn in a ratio of l 6.5, their strength then being 82 g/tex.
- a heater according to the invention was used in the spinning process of high strength filaments from a material having an intrinsic viscosity of 0.73. In this case it can be used either for reducing the molecule orientation with the same draw-off speed of the spun filaments or for maintaining the degree of molecule orientation with an increased draw-off speed.
- the present example is intended to illustrate the former possibility.
- the positions of the heater and spinning chamber were the same as in Example 1.
- a heater for use in the manufacture of spun plastics filaments which comprises two portions each of which has a truncated right polygonal pyramidal or truncated right conical internal surface that is open ended, the perimeters of the larger ends of the internal surfaces being congruent and the two portions meeting at their larger ends with the perimeters of the larger ends of the internal surfaces in register with one another, wherein the internal surface of one of the portions is heated and the internal surface of the other portion is thermally reflective.
- a heater as claimed in claim 1 wherein there is provided at the smaller end of the said one portion a screen arranged to reduce the effective area of the said smaller opening.
- a heater as claimed in claim I wherein the internal surface of each of the said portions is a truncated right conical surface.
- L is the total height of the heater
- d is the largest diameter of the heater taken at right angles to the axis
- d is the diameter of the smaller opening in the said other portion.
- a heater as claimed in claim I wherein the internal surface of the said other portion is highly polished or coated with a reflective foil.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Textile Engineering (AREA)
- Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE2115312A DE2115312C3 (de) | 1971-03-30 | 1971-03-30 | Beheizbarer Spinnschacht |
Publications (1)
Publication Number | Publication Date |
---|---|
US3741716A true US3741716A (en) | 1973-06-26 |
Family
ID=5803215
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00238846A Expired - Lifetime US3741716A (en) | 1971-03-30 | 1972-03-28 | Heater for use in the manufacture of plastics filaments |
Country Status (11)
Country | Link |
---|---|
US (1) | US3741716A (ro) |
BE (1) | BE781488A (ro) |
CA (1) | CA964422A (ro) |
CH (1) | CH539691A (ro) |
DD (1) | DD95903A5 (ro) |
DE (1) | DE2115312C3 (ro) |
FR (1) | FR2132171B1 (ro) |
GB (1) | GB1391471A (ro) |
IT (1) | IT950854B (ro) |
NL (1) | NL7203995A (ro) |
RO (1) | RO64788A (ro) |
Cited By (40)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2003024882A2 (fr) | 2001-09-17 | 2003-03-27 | Rhodianyl | Materiau comprenant une matrice inorganique telle que ciment, mortier, platre ou beton, renforcee par des microfibres |
US10089516B2 (en) | 2013-07-31 | 2018-10-02 | Digilens, Inc. | Method and apparatus for contact image sensing |
US10145533B2 (en) | 2005-11-11 | 2018-12-04 | Digilens, Inc. | Compact holographic illumination device |
US10156681B2 (en) | 2015-02-12 | 2018-12-18 | Digilens Inc. | Waveguide grating device |
US10185154B2 (en) | 2011-04-07 | 2019-01-22 | Digilens, Inc. | Laser despeckler based on angular diversity |
US10209517B2 (en) | 2013-05-20 | 2019-02-19 | Digilens, Inc. | Holographic waveguide eye tracker |
US10216061B2 (en) | 2012-01-06 | 2019-02-26 | Digilens, Inc. | Contact image sensor using switchable bragg gratings |
US10234696B2 (en) | 2007-07-26 | 2019-03-19 | Digilens, Inc. | Optical apparatus for recording a holographic device and method of recording |
US10241330B2 (en) | 2014-09-19 | 2019-03-26 | Digilens, Inc. | Method and apparatus for generating input images for holographic waveguide displays |
US10330777B2 (en) | 2015-01-20 | 2019-06-25 | Digilens Inc. | Holographic waveguide lidar |
US10359736B2 (en) | 2014-08-08 | 2019-07-23 | Digilens Inc. | Method for holographic mastering and replication |
US10423222B2 (en) | 2014-09-26 | 2019-09-24 | Digilens Inc. | Holographic waveguide optical tracker |
US10437051B2 (en) | 2012-05-11 | 2019-10-08 | Digilens Inc. | Apparatus for eye tracking |
US10437064B2 (en) | 2015-01-12 | 2019-10-08 | Digilens Inc. | Environmentally isolated waveguide display |
US10459145B2 (en) | 2015-03-16 | 2019-10-29 | Digilens Inc. | Waveguide device incorporating a light pipe |
US10545346B2 (en) | 2017-01-05 | 2020-01-28 | Digilens Inc. | Wearable heads up displays |
US10591756B2 (en) | 2015-03-31 | 2020-03-17 | Digilens Inc. | Method and apparatus for contact image sensing |
US10642058B2 (en) | 2011-08-24 | 2020-05-05 | Digilens Inc. | Wearable data display |
US10670876B2 (en) | 2011-08-24 | 2020-06-02 | Digilens Inc. | Waveguide laser illuminator incorporating a despeckler |
US10678053B2 (en) | 2009-04-27 | 2020-06-09 | Digilens Inc. | Diffractive projection apparatus |
US10690851B2 (en) | 2018-03-16 | 2020-06-23 | Digilens Inc. | Holographic waveguides incorporating birefringence control and methods for their fabrication |
US10690916B2 (en) | 2015-10-05 | 2020-06-23 | Digilens Inc. | Apparatus for providing waveguide displays with two-dimensional pupil expansion |
US10732569B2 (en) | 2018-01-08 | 2020-08-04 | Digilens Inc. | Systems and methods for high-throughput recording of holographic gratings in waveguide cells |
US10859768B2 (en) | 2016-03-24 | 2020-12-08 | Digilens Inc. | Method and apparatus for providing a polarization selective holographic waveguide device |
US10890707B2 (en) | 2016-04-11 | 2021-01-12 | Digilens Inc. | Holographic waveguide apparatus for structured light projection |
US10914950B2 (en) | 2018-01-08 | 2021-02-09 | Digilens Inc. | Waveguide architectures and related methods of manufacturing |
US10942430B2 (en) | 2017-10-16 | 2021-03-09 | Digilens Inc. | Systems and methods for multiplying the image resolution of a pixelated display |
US10983340B2 (en) | 2016-02-04 | 2021-04-20 | Digilens Inc. | Holographic waveguide optical tracker |
US11307432B2 (en) | 2014-08-08 | 2022-04-19 | Digilens Inc. | Waveguide laser illuminator incorporating a Despeckler |
US11378732B2 (en) | 2019-03-12 | 2022-07-05 | DigLens Inc. | Holographic waveguide backlight and related methods of manufacturing |
US11402801B2 (en) | 2018-07-25 | 2022-08-02 | Digilens Inc. | Systems and methods for fabricating a multilayer optical structure |
US11442222B2 (en) | 2019-08-29 | 2022-09-13 | Digilens Inc. | Evacuated gratings and methods of manufacturing |
US11448937B2 (en) | 2012-11-16 | 2022-09-20 | Digilens Inc. | Transparent waveguide display for tiling a display having plural optical powers using overlapping and offset FOV tiles |
US11460621B2 (en) | 2012-04-25 | 2022-10-04 | Rockwell Collins, Inc. | Holographic wide angle display |
US11480788B2 (en) | 2015-01-12 | 2022-10-25 | Digilens Inc. | Light field displays incorporating holographic waveguides |
US11513350B2 (en) | 2016-12-02 | 2022-11-29 | Digilens Inc. | Waveguide device with uniform output illumination |
US11543594B2 (en) | 2019-02-15 | 2023-01-03 | Digilens Inc. | Methods and apparatuses for providing a holographic waveguide display using integrated gratings |
US11681143B2 (en) | 2019-07-29 | 2023-06-20 | Digilens Inc. | Methods and apparatus for multiplying the image resolution and field-of-view of a pixelated display |
US11726332B2 (en) | 2009-04-27 | 2023-08-15 | Digilens Inc. | Diffractive projection apparatus |
US11747568B2 (en) | 2019-06-07 | 2023-09-05 | Digilens Inc. | Waveguides incorporating transmissive and reflective gratings and related methods of manufacturing |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4036070A1 (de) * | 1990-11-13 | 1992-05-14 | Hoechst Ag | Erhitzungsvorrichtung und verfahren zur herstellung schnellgesponnener filamente |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1881331A (en) * | 1930-12-24 | 1932-10-04 | Smith Wiloughby Statham | Apparatus for the continuous heat treatment of metals or alloys |
US3174537A (en) * | 1959-06-30 | 1965-03-23 | Thompson Ramo Wooldridge Inc | Electromagnetic radiant energy response apparatus |
US3285333A (en) * | 1962-10-17 | 1966-11-15 | Garrett Corp | Geometrically-spectrally selective radiator |
-
1971
- 1971-03-30 DE DE2115312A patent/DE2115312C3/de not_active Expired
-
1972
- 1972-03-24 NL NL7203995A patent/NL7203995A/xx not_active Application Discontinuation
- 1972-03-28 IT IT22525/72A patent/IT950854B/it active
- 1972-03-28 US US00238846A patent/US3741716A/en not_active Expired - Lifetime
- 1972-03-28 CH CH459372A patent/CH539691A/de not_active IP Right Cessation
- 1972-03-28 RO RO7270299A patent/RO64788A/ro unknown
- 1972-03-29 CA CA138,412A patent/CA964422A/en not_active Expired
- 1972-03-29 FR FR7211001A patent/FR2132171B1/fr not_active Expired
- 1972-03-30 GB GB1517872A patent/GB1391471A/en not_active Expired
- 1972-03-30 BE BE781488A patent/BE781488A/xx unknown
- 1972-03-30 DD DD161933A patent/DD95903A5/xx unknown
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1881331A (en) * | 1930-12-24 | 1932-10-04 | Smith Wiloughby Statham | Apparatus for the continuous heat treatment of metals or alloys |
US3174537A (en) * | 1959-06-30 | 1965-03-23 | Thompson Ramo Wooldridge Inc | Electromagnetic radiant energy response apparatus |
US3285333A (en) * | 1962-10-17 | 1966-11-15 | Garrett Corp | Geometrically-spectrally selective radiator |
Cited By (66)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2003024882A2 (fr) | 2001-09-17 | 2003-03-27 | Rhodianyl | Materiau comprenant une matrice inorganique telle que ciment, mortier, platre ou beton, renforcee par des microfibres |
US10145533B2 (en) | 2005-11-11 | 2018-12-04 | Digilens, Inc. | Compact holographic illumination device |
US10234696B2 (en) | 2007-07-26 | 2019-03-19 | Digilens, Inc. | Optical apparatus for recording a holographic device and method of recording |
US10725312B2 (en) | 2007-07-26 | 2020-07-28 | Digilens Inc. | Laser illumination device |
US11175512B2 (en) | 2009-04-27 | 2021-11-16 | Digilens Inc. | Diffractive projection apparatus |
US11726332B2 (en) | 2009-04-27 | 2023-08-15 | Digilens Inc. | Diffractive projection apparatus |
US10678053B2 (en) | 2009-04-27 | 2020-06-09 | Digilens Inc. | Diffractive projection apparatus |
US10185154B2 (en) | 2011-04-07 | 2019-01-22 | Digilens, Inc. | Laser despeckler based on angular diversity |
US11487131B2 (en) | 2011-04-07 | 2022-11-01 | Digilens Inc. | Laser despeckler based on angular diversity |
US10670876B2 (en) | 2011-08-24 | 2020-06-02 | Digilens Inc. | Waveguide laser illuminator incorporating a despeckler |
US11287666B2 (en) | 2011-08-24 | 2022-03-29 | Digilens, Inc. | Wearable data display |
US10642058B2 (en) | 2011-08-24 | 2020-05-05 | Digilens Inc. | Wearable data display |
US10216061B2 (en) | 2012-01-06 | 2019-02-26 | Digilens, Inc. | Contact image sensor using switchable bragg gratings |
US10459311B2 (en) | 2012-01-06 | 2019-10-29 | Digilens Inc. | Contact image sensor using switchable Bragg gratings |
US11460621B2 (en) | 2012-04-25 | 2022-10-04 | Rockwell Collins, Inc. | Holographic wide angle display |
US11994674B2 (en) | 2012-05-11 | 2024-05-28 | Digilens Inc. | Apparatus for eye tracking |
US10437051B2 (en) | 2012-05-11 | 2019-10-08 | Digilens Inc. | Apparatus for eye tracking |
US20230114549A1 (en) * | 2012-11-16 | 2023-04-13 | Rockwell Collins, Inc. | Transparent waveguide display |
US11448937B2 (en) | 2012-11-16 | 2022-09-20 | Digilens Inc. | Transparent waveguide display for tiling a display having plural optical powers using overlapping and offset FOV tiles |
US11815781B2 (en) * | 2012-11-16 | 2023-11-14 | Rockwell Collins, Inc. | Transparent waveguide display |
US11662590B2 (en) | 2013-05-20 | 2023-05-30 | Digilens Inc. | Holographic waveguide eye tracker |
US10209517B2 (en) | 2013-05-20 | 2019-02-19 | Digilens, Inc. | Holographic waveguide eye tracker |
US10089516B2 (en) | 2013-07-31 | 2018-10-02 | Digilens, Inc. | Method and apparatus for contact image sensing |
US10423813B2 (en) | 2013-07-31 | 2019-09-24 | Digilens Inc. | Method and apparatus for contact image sensing |
US11307432B2 (en) | 2014-08-08 | 2022-04-19 | Digilens Inc. | Waveguide laser illuminator incorporating a Despeckler |
US10359736B2 (en) | 2014-08-08 | 2019-07-23 | Digilens Inc. | Method for holographic mastering and replication |
US11709373B2 (en) | 2014-08-08 | 2023-07-25 | Digilens Inc. | Waveguide laser illuminator incorporating a despeckler |
US11726323B2 (en) | 2014-09-19 | 2023-08-15 | Digilens Inc. | Method and apparatus for generating input images for holographic waveguide displays |
US10241330B2 (en) | 2014-09-19 | 2019-03-26 | Digilens, Inc. | Method and apparatus for generating input images for holographic waveguide displays |
US10423222B2 (en) | 2014-09-26 | 2019-09-24 | Digilens Inc. | Holographic waveguide optical tracker |
US10437064B2 (en) | 2015-01-12 | 2019-10-08 | Digilens Inc. | Environmentally isolated waveguide display |
US11726329B2 (en) | 2015-01-12 | 2023-08-15 | Digilens Inc. | Environmentally isolated waveguide display |
US11740472B2 (en) | 2015-01-12 | 2023-08-29 | Digilens Inc. | Environmentally isolated waveguide display |
US11480788B2 (en) | 2015-01-12 | 2022-10-25 | Digilens Inc. | Light field displays incorporating holographic waveguides |
US10330777B2 (en) | 2015-01-20 | 2019-06-25 | Digilens Inc. | Holographic waveguide lidar |
US10527797B2 (en) | 2015-02-12 | 2020-01-07 | Digilens Inc. | Waveguide grating device |
US11703645B2 (en) | 2015-02-12 | 2023-07-18 | Digilens Inc. | Waveguide grating device |
US10156681B2 (en) | 2015-02-12 | 2018-12-18 | Digilens Inc. | Waveguide grating device |
US12013561B2 (en) | 2015-03-16 | 2024-06-18 | Digilens Inc. | Waveguide device incorporating a light pipe |
US10459145B2 (en) | 2015-03-16 | 2019-10-29 | Digilens Inc. | Waveguide device incorporating a light pipe |
US10591756B2 (en) | 2015-03-31 | 2020-03-17 | Digilens Inc. | Method and apparatus for contact image sensing |
US10690916B2 (en) | 2015-10-05 | 2020-06-23 | Digilens Inc. | Apparatus for providing waveguide displays with two-dimensional pupil expansion |
US11281013B2 (en) | 2015-10-05 | 2022-03-22 | Digilens Inc. | Apparatus for providing waveguide displays with two-dimensional pupil expansion |
US11754842B2 (en) | 2015-10-05 | 2023-09-12 | Digilens Inc. | Apparatus for providing waveguide displays with two-dimensional pupil expansion |
US10983340B2 (en) | 2016-02-04 | 2021-04-20 | Digilens Inc. | Holographic waveguide optical tracker |
US11604314B2 (en) | 2016-03-24 | 2023-03-14 | Digilens Inc. | Method and apparatus for providing a polarization selective holographic waveguide device |
US10859768B2 (en) | 2016-03-24 | 2020-12-08 | Digilens Inc. | Method and apparatus for providing a polarization selective holographic waveguide device |
US10890707B2 (en) | 2016-04-11 | 2021-01-12 | Digilens Inc. | Holographic waveguide apparatus for structured light projection |
US11513350B2 (en) | 2016-12-02 | 2022-11-29 | Digilens Inc. | Waveguide device with uniform output illumination |
US11586046B2 (en) | 2017-01-05 | 2023-02-21 | Digilens Inc. | Wearable heads up displays |
US10545346B2 (en) | 2017-01-05 | 2020-01-28 | Digilens Inc. | Wearable heads up displays |
US11194162B2 (en) | 2017-01-05 | 2021-12-07 | Digilens Inc. | Wearable heads up displays |
US10942430B2 (en) | 2017-10-16 | 2021-03-09 | Digilens Inc. | Systems and methods for multiplying the image resolution of a pixelated display |
US10914950B2 (en) | 2018-01-08 | 2021-02-09 | Digilens Inc. | Waveguide architectures and related methods of manufacturing |
US10732569B2 (en) | 2018-01-08 | 2020-08-04 | Digilens Inc. | Systems and methods for high-throughput recording of holographic gratings in waveguide cells |
US11726261B2 (en) | 2018-03-16 | 2023-08-15 | Digilens Inc. | Holographic waveguides incorporating birefringence control and methods for their fabrication |
US11150408B2 (en) | 2018-03-16 | 2021-10-19 | Digilens Inc. | Holographic waveguides incorporating birefringence control and methods for their fabrication |
US10690851B2 (en) | 2018-03-16 | 2020-06-23 | Digilens Inc. | Holographic waveguides incorporating birefringence control and methods for their fabrication |
US11402801B2 (en) | 2018-07-25 | 2022-08-02 | Digilens Inc. | Systems and methods for fabricating a multilayer optical structure |
US11543594B2 (en) | 2019-02-15 | 2023-01-03 | Digilens Inc. | Methods and apparatuses for providing a holographic waveguide display using integrated gratings |
US11378732B2 (en) | 2019-03-12 | 2022-07-05 | DigLens Inc. | Holographic waveguide backlight and related methods of manufacturing |
US11747568B2 (en) | 2019-06-07 | 2023-09-05 | Digilens Inc. | Waveguides incorporating transmissive and reflective gratings and related methods of manufacturing |
US11681143B2 (en) | 2019-07-29 | 2023-06-20 | Digilens Inc. | Methods and apparatus for multiplying the image resolution and field-of-view of a pixelated display |
US11899238B2 (en) | 2019-08-29 | 2024-02-13 | Digilens Inc. | Evacuated gratings and methods of manufacturing |
US11442222B2 (en) | 2019-08-29 | 2022-09-13 | Digilens Inc. | Evacuated gratings and methods of manufacturing |
US11592614B2 (en) | 2019-08-29 | 2023-02-28 | Digilens Inc. | Evacuated gratings and methods of manufacturing |
Also Published As
Publication number | Publication date |
---|---|
CH539691A (de) | 1973-07-31 |
DE2115312A1 (de) | 1972-10-19 |
NL7203995A (ro) | 1972-10-03 |
DE2115312B2 (de) | 1974-10-31 |
FR2132171B1 (ro) | 1975-10-24 |
IT950854B (it) | 1973-06-20 |
RO64788A (ro) | 1982-02-26 |
FR2132171A1 (ro) | 1972-11-17 |
GB1391471A (en) | 1975-04-23 |
BE781488A (fr) | 1972-10-02 |
CA964422A (en) | 1975-03-18 |
DE2115312C3 (de) | 1975-06-26 |
DD95903A5 (ro) | 1973-02-20 |
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