Fourier transform type spectrophotometer to control a speed of a moving mirror

• US 10,502,626 B2
• Filed: 03/13/2015
• Issued: 12/10/2019
• Est. Priority Date: 03/13/2015
• Status: Active Grant

• Current Assignee: Shimadzu Corporation
• Original Assignee: Shimadzu Corporation
• Inventors: Kamikake, Tadafumi
• Primary Examiner(s): LaPage, Michael P
• Application Number:
  US15/558,165
• Publication Number:
  US 20180073927A1
• Time in Patent Office: 1,733 Days
• CPC Class Codes: G01J 2003/064 Use of other elements for scan, e.g. mirror, fixed grating
• CPC Class Codes: G01J 3/0202 Mechanical elements; Supports for optical elements
• CPC Class Codes: G01J 3/027 Control of working procedures of a spectrometer; Failure detection; Bandwidth calculation
• CPC Class Codes: G01J 3/0275 making use of sensor-related data, e.g. for identification of sensor parts or optical elements
• CPC Class Codes: G01J 3/0289 Field-of-view determination; Aiming or pointing of a spectrometer; Adjusting alignment; Encoding angular position; Size of measurement area; Position tracking
• CPC Class Codes: G01J 3/06 Scanning arrangements arrangements for order-selection
• CPC Class Codes: G01J 3/4535 Devices with moving mirror G01J3/4532 takes precedence
• CPC Class Codes: G01N 21/27 using photo-electric detection G01N21/31 takes precedence; circuits for computing concentration logarithmic circuits G06G7/24; photometric circuits in general G01J

Abstract

A Fourier transform type spectrophotometer capable of stably controlling a speed of a moving mirror comprises a movable unit to which a moving mirror is fixed, outside-force-applying means configured to apply external force larger than movement resistance of the movable unit to the movable unit, a driving source configured to apply positive or negative driving force along the moving direction of the movable unit to the movable unit, a speed measurement unit configured to measure the speed of the movable unit, and a driving force control unit configured to control the driving force of the driving source so that the movable unit is moved in a predetermined manner based on the speed, wherein a rate of fluctuation of the driving force is suppressed by operating in a state in which the driving force of the driving source is high due to the external force to thereby stabilize the control.

Claims

1. A Fourier transform type spectrophotometer comprising:

a linear guide along which a moving mirror is movable;

a movable unit to which the moving mirror is fixed, the movable unit being movable on the linear guide;

an elastic member configured to always apply external force to the movable unit in a direction along the linear guide, wherein the external force is larger than movement resistance on the linear guide of the movable unit;

a driving source configured to apply positive or negative driving force along a moving direction of the movable unit to the movable unit; and

a controller configured to measure a moving speed of the movable unit and control the driving force of the driving source so that the movable unit is moved in a predetermined manner based on the moving speed.

2. The Fourier transform type spectrophotometer as recited in claim 1,

wherein the elastic member is rubber.

3. The Fourier transform type spectrophotometer as recited in claim 1, wherein the driving source is a voice coil motor or a hydraulic device.

4. The Fourier transform type spectrophotometer as recited in claim 1, wherein the external force is larger than twice the movement resistance of the movable unit.

5. The Fourier transform type spectrophotometer as recited in claim 1, wherein the elastic member is a spring.

6. A Fourier transform type spectrophotometer, comprising:

a linear guide along which a moving mirror is movable;

a movable unit to which the moving mirror is fixed, the movable unit being movable on the linear guide;

an inclination providing structure having a first part and a second part spaced part from the first part in a horizontal direction, the first part having a vertical height higher than a vertical height of the second part, wherein the inclination providing structure is configured to incline the linear guide such that component force of gravity of the movable unit in a direction along the linear guide is greater than movement resistance on the linear guide of the movable unit;

a driving source configured to apply positive or negative driving force along a moving direction of the movable unit on the linear guide to the movable unit; and

a controller configured to measure a moving speed of the movable unit and control the driving force of the driving source so that the movable unit is moved on the linear guide in a predetermined manner based on the moving speed.

7. The Fourier transform type spectrophotometer as recited in claim 6, wherein the driving source is a voice coil motor or a hydraulic device.