Related Experiment Video
Updated: Jul 6, 2026
07:22
Fabrication of a Low-Cost, Fiber-Coupled, and Air-Spaced Fabry-Pérot Etalon
Published on: February 3, 2023
Off-axis pivot mounting for aberration-corrected concave gratings at normal incidence
1Department of Electronics and Informatics, Istituto Nazionale per la Fisica della Materia, University of Padova, Via Gradenigo 6yA, 35131 Padua, Italy. poletto@dei.unipd.it
Applied Optics
|March 14, 2008
Summary
This study presents an off-axis pivot-point mounting for toroidal uniform line-space (TULS) and spherical varied line-space (SVLS) gratings. Optimal pivot point placement minimizes spectral defocusing and aberrations for improved optical performance.
Area of Science:
- Optics
- Spectroscopy
- Optical Engineering
Background:
- Toroidal uniform line-space (TULS) and spherical varied line-space (SVLS) gratings are crucial optical components.
- Efficient spectral scanning requires precise grating mounting and rotation.
- Existing mounting methods may introduce spectral defocusing and aberrations.
Purpose of the Study:
- To present an off-axis pivot-point mounting strategy for TULS and SVLS gratings.
- To determine optimal pivot point locations for monochromator and spectrometer applications.
- To analyze the impact of pivot arm length on spectral defocusing.
Main Methods:
- Investigated spectral scanning by rotating gratings around a pivot point.
- Defined optimal pivot point locations based on application (monochromator/spectrometer).
- Calculated optimum pivot arm length to minimize spectral defocusing.
Main Results:
- Pivot points for TULS and SVLS gratings are positioned on opposite sides of the grating normal.
- Optimal pivot point location depends on whether the system is a monochromator or spectrometer.
- Spectral focusing performance is comparable between TULS and SVLS gratings.
- SVLS gratings offer potential for reduced spatial aberrations compared to TULS gratings.
Conclusions:
- The proposed off-axis pivot-point mounting effectively enables spectral scanning for TULS and SVLS gratings.
- Careful selection of the pivot point and arm length minimizes spectral defocusing and aberrations.
- SVLS gratings present an advantage in reducing spatial aberrations in certain optical designs.
Related Concept Videos
01:15Unsymmetric Bending - Angle of Neutral Axis
Unsymmetrical bending occurs when a structural member is subjected to bending moments in a plane that does not align with the member's principal axes. This scenario typically arises in beams and other structural components when loads are applied at non-ideal angles, introducing complexities in stress analysis.
When a bending moment is applied at an angle θ concerning the vertical axis of a symmetrical member, it can be resolved into components along the member's principal centroidal axes. The...
When a bending moment is applied at an angle θ concerning the vertical axis of a symmetrical member, it can be resolved into components along the member's principal centroidal axes. The...
01:16Eccentric Axial Loading in a Plane of Symmetry
Eccentric axial loading occurs when an axial load is applied away from the centroidal axis of a structural member. This scenario is common in engineering, where structural elements may not be directly aligned due to various design or functional requirements.
01:26Rotational Motion about a Fixed Axis
A rigid body's rotation around a fixed axis makes every point within it trace a circular path around a specific line or point. The term given to this type of spinning is defined by the angular position, symbolized by the angle θ. This angle is gauged from a static reference line to the revolving object. From this angular position, any variation is referred to as angular displacement, denoted by dθ. The extent of this displacement can be calculated in degrees, radians, or revolutions, where one...
01:20Moment of Inertia about an Arbitrary Axis
The moment of inertia is typically associated with principal axes, but it can also be computed for any random axis. When an arbitrary axis is under consideration, the moment of inertia is determined by integrating the mass distribution of the object along that specific axis. It is crucial in applications like the design of machinery, where components rotate about various axes, and balance and stability are essential.
In this scenario, the perpendicular distance between the chosen arbitrary axis...
In this scenario, the perpendicular distance between the chosen arbitrary axis...
01:27Curvilinear Motion: Normal and Tangential Components
When a car traverses a curved road, its motion can be elucidated by breaking it down into tangential and normal components. The car-centric coordinates attached to the vehicle move with it.
The positive direction of the t-axis aligns with the increasing position of the car along the curved path, denoted by the unit vector ut. Simultaneously, the n-axis, perpendicular to the t-axis, dissects the curved path into differential arc segments, each forming the arc of a circle with a radius of...
The positive direction of the t-axis aligns with the increasing position of the car along the curved path, denoted by the unit vector ut. Simultaneously, the n-axis, perpendicular to the t-axis, dissects the curved path into differential arc segments, each forming the arc of a circle with a radius of...
01:11Rotation of Asymmetric Top
By definition, a spherically symmetric body has the same moment of inertia about any axis passing through its center of mass. This situation changes if there is no spherical symmetry. Since most rigid bodies are not spherically symmetric, these require special treatment.
The relationship between the angular momentum of any rigid body and its angular velocity, both of which are vectors, involves the moment of inertia. The moment of inertia is a scalar quantity only for spherically symmetric...
The relationship between the angular momentum of any rigid body and its angular velocity, both of which are vectors, involves the moment of inertia. The moment of inertia is a scalar quantity only for spherically symmetric...