Optical analyzer

Patent metadata

Field	Value
Publication number	US-2016234904-A1
Application number	US-201615015810-A
Country	US
Kind code	A1
Filing date	Feb 4, 2016
Priority date	Feb 9, 2015
Publication date	Aug 11, 2016
Grant date	—

Abstract

Provided is an optical analyzer for performing a feedback control on the amount of light emitted from an LED as a light source, in which the configuration of an optical system is made simple and the degree of freedom in optical system arrangement is secured. An optical member 2 for focusing most of light while discharging part of the light as unfocused light is provided on an optical path from a light casting unit 1 to a sample cell 3. The optical member 2 can be achieved with a simple configuration, for example, two ball lenses spaced apart by a predetermined distance from each other. The light focused by the optical member 2 is cast as measurement light into the sample cell 3. Meanwhile, a second photodetector 5 is arranged at a position where the unfocused light reaches. The second photodetector 5 generates a detection signal in accordance with the amount of light that has entered the second photodetector 5 as monitored light, and a drive current to be supplied to an LED is controlled through a drive current controlling unit 6 and a current source 7 such that the amount of light is maintained at a fixed level.

First claim

1 . An optical analyzer for analyzing a target sample by casting light from a light casting unit into or onto the sample and introducing light obtained from the sample in response to the cast light into a photodetector, the light casting unit including a light-emitting semiconductor device as a light source, the optical analyzer comprising:
a) an optical member for focusing received light on the sample while generating unfocused light without focusing part of the received light, the optical member being arranged on an optical path from the light casting unit to the sample; b) a second photodetector arranged at a position where the unfocused light generated by the optical member reaches; and c) a controlling unit for controlling a drive current to be supplied to the light-emitting semiconductor device based on an intensity signal generated by the second photodetector such that an amount of light is at a fixed level.

2 . The optical analyzer according to claim 1 , wherein
the optical member includes a plurality of lenses spaced apart by a predetermined distance from each other.

3 . The optical analyzer according to claim 1 , wherein
the optical member includes an aspherical lens.

Assignees

• Shimadzu Corp

Inventors

• Nagai Yusuke
• Ogawa Keisuke
• Watanabe Masato
• Jingu Kumiko
• Fujiwara Masanori
• Yamazaki Tomoyuki

Classifications

• G01N21/33 Primary

  using ultraviolet light (G01N21/39 takes precedence) · CPC title

• G01N2201/0692

  Regulated sources; stabilised supply · CPC title

• G01N2201/0621

  Supply · CPC title

• G01N21/01 Primary

  Arrangements or apparatus for facilitating the optical investigation · CPC title

• G01N2201/0695

  Supply to maintain constant beam intensity · CPC title