Microscope Illumination Using Light Diffusing Element

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional microscope apparatuses face limitations in restricting the pupil conjugate image with a light shielding element that moves in one plane, restricting the variable power range for oblique illumination due to changes in magnification.

Innovation Solution

The microscope apparatus incorporates a light diffusing element and a light shielding element, with specific optical properties and configurations, including a condenser lens with aspheric surfaces or a lens array, to ensure the entrance pupil is filled with illumination light regardless of magnification, allowing suitable restriction of the pupil conjugate image.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a light shielding element is moved in one plane to restrict the pupil conjugate image, then the structure is simple, but the variable power range for oblique illumination is restricted when magnification changes

Engineering Contradiction:
Improvestructure simplicityVSAvoidvariable power range
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The patent introduces a light diffusing element that creates a virtual light source at a different spatial dimension (distance D from the light shielding element), transforming the problem from a 2D plane movement constraint to a 3D spatial configuration. This allows the light shielding element to effectively restrict the pupil conjugate image across multiple magnification levels without requiring complex multi-plane movement mechanisms.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Illumination intensity

If a light shielding element is positioned to restrict the pupil conjugate image at one magnification, then the illumination is effective at that magnification, but the entrance pupil cannot be filled with illumination light at other magnifications

Engineering Contradiction:
Improveillumination effectivenessVSAvoidmagnification adaptability
Core Design Contradiction:
Illumination intensityVSAdaptability or versatility

Solution Approach 1:

The light diffusing element acts as an intermediary between the light source and the light shielding element. It creates a virtual light source that, when combined with the light shielding element at distance D, produces a pupil conjugate image that can be effectively restricted across different magnifications while ensuring the entrance pupil is filled with illumination light.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Ease of operation

If the light shielding element is moved in one plane, then the control is simple, but the pupil conjugate image cannot be suitably restricted across varying magnifications

Engineering Contradiction:
Improvecontrol simplicityVSAvoidpupil conjugate image restriction precision
Core Design Contradiction:
Ease of operationVSManufacturing precision

Solution Approach 1:

The patent changes the parameter of light source positioning by introducing distance D between the light shielding element and the light diffusing element. This parameter change creates a virtual light source that moves in correspondence with magnification changes, allowing the light shielding element to precisely restrict the pupil conjugate image across varying magnifications while maintaining simple one-plane movement control.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This configuration enables effective oblique illumination across varying magnifications, suppressing glare and enhancing contrast for phase objects by adjusting the light shielding rate and positioning of the light diffusing element.

Implementation Method 1

a light diffusing element (23) having a diffusion surface which diffuses the luminous flux transmitted without being shielded by the light shielding plate (22)

Methodology Applied
Scientific EffectLight diffusion: Scattering

Implementation Method 2

a condenser lens which condenses the light emitted from the surface light emitter and irradiates the sample with the condensed light

Methodology Applied
Scientific EffectLight condensation: Focusing

Implementation Method 3

the condenser lens includes at least one surface formed in an aspheric shape

Methodology Applied
Scientific EffectAspheric focusing: Lens

Data Source

PatentEP2453284B1microscope
Publication Date: 2020.10.21 NIKON CORP
  • EP2453284B1 patent drawingFigure 1
  • EP2453284B1 patent drawingFigure 2
  • EP2453284B1 patent drawingFigure 3

AI summary

To provide a microscope apparatus including an illumination apparatus which is capable of, regardless of the observation magnification of an imaging optical system, filling the entrance pupil of the imaging optical system with illumination light, and suitably restricting the conjugate image of the entrance pupil of the imaging optical system by a light shielding element. A microscope apparatus 1 is configured by including: an illumination apparatus 2 which includes a surface light emitter (light guide plate 21) having a light emitting surface as a planar light-emitting region and irradiates a sample S with light emitted from the light guide plate 21; an objective lens 31 which condenses light from the sample S; and an imaging optical system 3 which includes a variable power lens group 32 configured to form an image of the sample S by changing the magnification of the image of the sample S. In the microscope apparatus 1, the illumination apparatus 2 includes a light shielding plate 22, as a light shielding element, which is arranged on the sample side of the light emitting surface of the light guide plate 21 and shields a part of a luminous flux emitted from the light emitting surface, and a light diffusing element 23 which is arranged on the sample side of the light shielding plate 22 and diffuses light from the light guide plate 21.