Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Article having a birefringent surface for use as a blur filter

A fuzzy filter, birefringence technology, applied in instruments, polarizing components, optics, etc., can solve problems that are difficult to handle, easy to break, and cannot be loaded into mobile phones or personal digital assistants with digital cameras

Inactive Publication Date: 2008-01-23
3M INNOVATIVE PROPERTIES CO
View PDF1 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Typically, this stack of discrete sheets is far too thick (typically 2 mm or more in thickness) to be incorporated into a cell phone or personal digital assistant with a digital camera
Additionally, quartz sheets can be expensive for some implementations and tend to break easily, making them difficult to handle and not particularly suitable for use in mobile devices

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Article having a birefringent surface for use as a blur filter
  • Article having a birefringent surface for use as a blur filter
  • Article having a birefringent surface for use as a blur filter

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0135] Example 1 - Preparation of Oriented Microstructured Films

[0136] Polyethylene terephthalate (PET) with an intrinsic viscosity (I.V.) of 0.74 (available from Eastman Chemical Company, Kingsport, Tennessee, USA) was used in this example.

[0137] The PET pellets were dried to remove residual moisture and loaded into the extruder hopper under a nitrogen purge. PET was extruded in the extruder and the melter assembly connected thereto up to a temperature profile of 232°C to 282°C at the die (where the die was set at 282°C). The pressure of the melter assembly is continuously monitored and averaged at the last of a plurality of monitoring locations located along the melter assembly, and the die is then brought in close proximity to the tool on which the polymer film will be formed (the tool Simultaneously, the opposite first surface of the film is structured).

[0138] The tool was a structured ribbon of nickel alloy of unknown composition (manufactured by 3M Company) wi...

Embodiment 2

[0145] Embodiment 2--double-layer microstructured fuzzy filter

[0146] To create the microstructure in film 1, the unoriented (amorphous state) cast PEN material was directly cut into the following dimensions by diamond turning on a lathe before stretching: pitch of prisms on one surface of the film is about 89 microns, the apex angle is about 86°, one side of its cross-sectional triangle is inclined at 4° with respect to the horizontal line of the film substrate, and the side opposite to the side is inclined at 0° with respect to the vertical line, and Its depth is 6.5 microns. The obtained film was uniaxially stretched under the condition that the stretch ratio was 3, and the prismatic replication surface had the following dimensions and characteristics after stretching: the pitch was 49.8 microns, the apex angle was about 86°, and its cross-section was triangular. One side was inclined at 4° with respect to the horizontal of the film substrate and the opposite side was in...

Embodiment 3

[0152] Example 3 - two-dimensional (2D) controllable beam splitting

[0153] Before stretching, the film sample had a prismatic surface structure with an apex angle of about 90°, one side of its cross-sectional triangle inclined at 30° with respect to the horizontal line of the film substrate, and The opposite side is inclined at 30° relative to the vertical, and the prism pitch is 25 microns.

[0154] The film sample is uniaxially stretched under the condition that the uniaxial stretching ratio is 6, and the prismatic replication surface obtained after stretching has the following dimensions and characteristics: the pitch is 14.1 microns, and the apex angle is about 92°, which One side of the cross-sectional triangle was inclined at 28° relative to the horizontal of the film substrate and the opposite side was inclined at 30° relative to vertical, and had a depth of about 3.6 microns. Refractive index was measured on the back side of the stretched film using a Metricon prism...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
Thicknessaaaaaaaaaa
Thicknessaaaaaaaaaa
Login to View More

Abstract

An optical low pass filter or blur filter, and method of making the filters, using an article having a birefringent surface for refracting incoming light when used with an image sensor. The birefringent surface of the article, such as a film, is structured or tilted such that, when the blur filter is placed within an optical path between a lens and the image sensor, the birefringent surface causes refraction of a light signal in the optical path into multiple light signals each being incident upon different sub-pixels within the pixels in the image sensor to prevent or reduce artifacts, such as undesirable color moire effects, in the resulting digital image.

Description

technical field [0001] The present invention relates to an article having a birefringent surface inclined with respect to an optical path, and a method of manufacturing the article, wherein the article is used as a blur filter for use with an image sensor. The article has a surface having at least one electromagnetically anisotropic birefringent geometric feature for refracting an electromagnetic signal, such as an optical signal. Background technique [0002] Photo color distortion and color fringing that occur in digital imaging are caused by the interaction between the image mode and the image color sensor mode. These adverse effects are produced by sharp edges (indicating abrupt changes in color) and repetitive image features at the scale of a single pixel sensor. Since the real-world pattern spacing will never exactly match that of the digital sensor pattern, overly heavy colors will vary across the space of the image with the magnitude of the phase difference between ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): G02B27/46G02B5/30
CPCG02B5/3083G02B27/46G02B27/48G02B1/08
Inventor 罗尔夫·W·比尔纳特罗伯特·L·布劳特威廉·W·梅里尔
Owner 3M INNOVATIVE PROPERTIES CO
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com