CN102735596A - Laser particle sizer for eliminating center spot of receiving plane - Google Patents
Laser particle sizer for eliminating center spot of receiving plane Download PDFInfo
- Publication number
- CN102735596A CN102735596A CN2012102189663A CN201210218966A CN102735596A CN 102735596 A CN102735596 A CN 102735596A CN 2012102189663 A CN2012102189663 A CN 2012102189663A CN 201210218966 A CN201210218966 A CN 201210218966A CN 102735596 A CN102735596 A CN 102735596A
- Authority
- CN
- China
- Prior art keywords
- phase delay
- delay device
- laser particle
- light
- receiving plane
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Abstract
The invention relates to a laser particle sizer for eliminating a center spot of a receiving plane. In the prior art, the laser particle sizer concurrently receives an incident light signal and a scattered light signal, and the incident light is converged in the center spot of the receiving plane so as to provide a large impact on the scattered light. With the present invention, the problem in the prior art is solved. The laser particle sizer comprises a laser emitting system, a phase delay device, a receiving lens, a photoelectric detector and a processing circuit. The phase delay device is arranged between the laser emission system and sample particles, and covers 1/2 of area of the incident wave plane. With the phase delay device, the light wave phase of the light passing through the phase delay device is delayed by odd times of pi. After the incident light is converged through the receiving lens, the central dark spot is formed on the focal point of the receiving plane so as to eliminate the influence on the scattered light.
Description
Technical field
The invention belongs to the testing tool technical field, relate to a kind of laser particle size method of testing that can eliminate the incident light influence, be used to eliminate the influence that the central bright spot of incident light on receiving plane causes scattered light.
Background technology
At present, laser particle analyzer has become the grain graininess surveying instrument of widespread use, and it is according to the scattering of light principle work.In order to obtain the scattered signal of particle, generally adopt the laser beam irradiation particulate samples of single wavelength, receive signal in the focal plane (or equivalent focal plane) of receiver lens.Incident light is focused at the back focus (or equivalent back focus) of receiver lens.In real system; The incident light that is focused on the back focus (or equivalent back focus) through lens is not a desirable point, always becomes a central bright spot, and the intensity of this central bright spot is very big; The scattered light intensity that surpasses far away, the influence of incident light is bigger at little scattering angle place.With the signal of no particulate samples as a setting, the signal subtracting background when containing particulate samples can obtain scattered signal.When having particle, incident light is weakened by the particle scattering, and the background that therefore cuts is bigger than actual value.Especially at little scattering angle place, the scattered signal that obtains even be negative value is revised difficulty.
On the other hand, this intensity of central bright spot is very big, generally will punching it seen through or adopt reflection unit to reflex to other position to it in the middle of the photodetector, and can to reach signal saturated otherwise be positioned near the back focus probe unit.Therefore, the photodetector of laser particle analyzer is generally according to instrument parameter customization, complex process, processing difficulties.
Summary of the invention
The object of the invention provides a kind of laser particle analyzer that can eliminate the influence of receiving plane central bright spot, mainly solves following problem:
1, existing laser particle analyzer receives incident light and scattered light simultaneously when receiving signal, and the central bright spot of incident light on receiving plane is big to stray light effects, is not easy to eliminate, and the measurement result deviation is bigger;
2, make relatively difficulty of special photoelectric sensitive detection parts.
Technical scheme of the present invention:
The laser particle analyzer that can eliminate the receiving plane central bright spot provided by the invention; Comprise laser transmitting system (1), phase delay device (2), receiver lens (4) and photodetector (5) and treatment circuit successively; After wherein phase delay device (2) was positioned over laser transmitting system, particulate samples to be measured (3) was placed between phase delay device (2) and the receiver lens (4).
Described phase delay device can make the phase delay that the odd of π is arranged through its light.
The light wave that laser transmitting system sends has 50% through phase delay device (2), and phase place is postponed the odd of π.According to the light wave superposition principle, form blackening in receiver lens back focus (or convergent point), can ignore its influence to scattered light.The testing sample grain diameter is generally at micron order, and the laser particle size test philosophy is to low concentrations of particulates, and the scattered signal of variable grain is uncorrelated, is irrelevant stack receiving on the plane, i.e. light intensity addition.Therefore, add the phase delay device front and back particle scattered signal is not had influence.
Advantage of the present invention and good effect:
The laser particle analyzer of eliminating the receiving plane central bright spot provided by the invention, phase delay device (2) place between laser transmitting system and the appearance mouthful particle (3), cover 50% light field scope, make light wave that the odd phase delay of π arranged.Therefore incident light forms central blackening receiving on the focus, and photodetector receives has only scattered light signal; Avoid to simplify photoelectric detector processing at punching of detector central authorities or employing reflection unit.
Description of drawings
Fig. 1 is the laser particle analyzer structural representation that can eliminate the receiving plane central bright spot provided by the invention.
Among the figure, 1 laser transmitting system, 2 phase delay device, 3 particulate samples to be measured, 4 receiver lenss, 5 photodetectors.
Embodiment
Embodiment
As shown in Figure 1.This laser particle analyzer comprises laser transmitting system (1), phase delay device (2), particulate samples to be measured (3), receiver lens (4) and photodetector (5) and treatment circuit in order.After phase delay device (2) was placed on laser transmitting system, particulate samples to be measured (3) was placed between phase delay device (2) and the receiver lens (4).
Laser transmitting system (1) has spatial filtering, expands bundle and collimator apparatus, and effect provides collimated light beam.Will carry out centering to light path before measuring, promptly launching spot should be adjusted to systematic optical axis and overlap.
The laser that is sent by laser transmitting system (1) becomes directional light behind beam-expanding collimation, 50% light wave makes the odd of the phase delay π or the π of light field through phase delay device.Scattering takes place at particulate samples to be measured (3) in this light wave and other 50% light-wave irradiation without phase delay.Photodetector (5) is placed on the back focal plane (or convergence plane) of receiver lens (4), by photodetector (5) measuring light intensity distribution signal.Scattered light intensity distributes unique corresponding with size distribution, can get size-grade distribution through data algorithm.
Incident light forms central blackening at receiving plane, can ignore its influence to scattered light.
Claims (3)
1. the laser particle analyzer that can eliminate the receiving plane central bright spot; It is characterized in that this laser particle analyzer comprises laser transmitting system (1), phase delay device (2), receiver lens (4) and photodetector (5) and treatment circuit successively; After wherein phase delay device (2) was positioned over laser transmitting system, particulate samples to be measured (3) was placed between phase delay device (2) and the receiver lens (4).
2. the laser particle analyzer of elimination receiving plane central bright spot according to claim 1 is characterized in that described phase delay device can make has the odd of π through its light phase delay.
3. according to the laser particle analyzer of claim 1,2 described elimination receiving plane central bright spot, it is characterized in that incident light after receiver lens is assembled, locates to form blackening in back focus (convergent point).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012102189663A CN102735596A (en) | 2012-06-28 | 2012-06-28 | Laser particle sizer for eliminating center spot of receiving plane |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012102189663A CN102735596A (en) | 2012-06-28 | 2012-06-28 | Laser particle sizer for eliminating center spot of receiving plane |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102735596A true CN102735596A (en) | 2012-10-17 |
Family
ID=46991487
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012102189663A Pending CN102735596A (en) | 2012-06-28 | 2012-06-28 | Laser particle sizer for eliminating center spot of receiving plane |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102735596A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104568682A (en) * | 2013-10-18 | 2015-04-29 | 中国航天科工集团第三研究院第八三五八研究所 | Design method of laser particle analyzer optical system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5459576A (en) * | 1994-01-24 | 1995-10-17 | Display Inspection Systems, Inc. | Differential phase contrast inspection system |
| CN2251721Y (en) * | 1995-08-28 | 1997-04-09 | 周定益 | Laser tester for investigating particle size |
| CN201004044Y (en) * | 2006-04-18 | 2008-01-09 | 周定益 | Laser granularity distribution tester |
| CN201622228U (en) * | 2009-11-26 | 2010-11-03 | 上海理工大学 | Dynamic polarized light scattered grain measuring device |
| CN201903495U (en) * | 2010-12-07 | 2011-07-20 | 上海理工大学 | Multi-sample cell laser particle sizer |
-
2012
- 2012-06-28 CN CN2012102189663A patent/CN102735596A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5459576A (en) * | 1994-01-24 | 1995-10-17 | Display Inspection Systems, Inc. | Differential phase contrast inspection system |
| CN2251721Y (en) * | 1995-08-28 | 1997-04-09 | 周定益 | Laser tester for investigating particle size |
| CN201004044Y (en) * | 2006-04-18 | 2008-01-09 | 周定益 | Laser granularity distribution tester |
| CN201622228U (en) * | 2009-11-26 | 2010-11-03 | 上海理工大学 | Dynamic polarized light scattered grain measuring device |
| CN201903495U (en) * | 2010-12-07 | 2011-07-20 | 上海理工大学 | Multi-sample cell laser particle sizer |
Non-Patent Citations (1)
| Title |
|---|
| 吴新生: "《河工模型量测与控制技术》", 31 March 2010, article "《河工模型量测与控制技术》，吴新生，正文第95页，中国水利水电出版社，2010年3月", pages: 95 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104568682A (en) * | 2013-10-18 | 2015-04-29 | 中国航天科工集团第三研究院第八三五八研究所 | Design method of laser particle analyzer optical system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN201083677Y (en) | Aerosol granule optical detection system | |
| CN106568762A (en) | Scanning type laser induced spectrum surface range analysis and detection system | |
| CN102353621B (en) | Measuring device and method of light scattering particles | |
| US8705030B2 (en) | Optical sample detection system and sample analysis device | |
| US20080186490A1 (en) | Irradiation unit for a flow-cytometry-based analytical instrument and analytical instrument including the same | |
| CN104865576B (en) | A kind of compact ultra-short pulse laser long-distance ranging system and its distance-finding method | |
| CN102288523B (en) | Granular grain diameter distribution measuring device based on linear array CCD (charge-coupled device) | |
| CN201622345U (en) | Laser distance measurement device | |
| WO2009095679A3 (en) | Device and method for measuring scattering of radiation | |
| CN101629903A (en) | Optical system of scattering-type cloud particle detector | |
| CN105652261A (en) | Laser radar optical system and laser radar | |
| CN202210068U (en) | Single light source and double light beam laser particle analyzer | |
| CN102221450A (en) | Tracking-pointing deviation measurement device for laser system | |
| CN102183359B (en) | Method and device for detecting collimation of light beams | |
| CN102928831A (en) | Laser measuring bare engine system | |
| CN104180901A (en) | Transmittance spectrum measurement device and method for ultra-narrow band filter | |
| CN102243098A (en) | In-situ test system of strong laser beam quality | |
| CN112903547B (en) | High-concentration cloud and mist particle concentration measuring device based on double light sources | |
| CN107064908A (en) | A kind of multi-wavelength polarizes Raman lidar beam splitting system | |
| CN112859099B (en) | High-precision ranging system based on real-time compensation of annular separator in cloud and fog environment | |
| CN101368899A (en) | Single-beam double-lens laser particle analyzer | |
| CN102735596A (en) | Laser particle sizer for eliminating center spot of receiving plane | |
| CN102590051B (en) | Oblique incident laser particle analyzer | |
| CN201277938Y (en) | Single-beam double-lens laser particle analyzer | |
| US20220412865A1 (en) | Detection device and method for tiny particles in liquid |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C12 | Rejection of a patent application after its publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20121017 |