Device and method for measuring opening and closing delay time of mechanical shutter of ICP spectrum analyzer

Abstract

The invention discloses a device for measuring the opening and closing delay time of a mechanical shutter of an ICP spectrum analyzer, which comprises an upper computer, an FPGA circuit board, a light source, the mechanical shutter and a photosensitive diode, and the light source, the mechanical shutter and the photosensitive diode are sequentially arranged on the same horizontal line; the upper computer sends an instruction to the FPGA circuit board, the FPGA circuit board controls opening and closing of the mechanical shutter to control different exposure integral times of the photosensitive diode, the opening and closing delay time of the mechanical shutter is calculated by collecting light intensity signals received by the photosensitive diode, opening and closing delay time information of each time is sent to the upper computer, and the method is simple and easy to implement. The device is easy to operate, improves the measurement efficiency, and guarantees the accuracy and reliability of a measurement result.

Description

Technical Field

[0001] The invention relates to the technical field of ICP spectrum analysis, and in particular to a device and method for measuring the opening and closing lag time of a mechanical shutter of an ICP spectrum analyzer. Background Art

[0002] Background introduction of related technology: ICP spectrometer (Inductively Coupled Plasma Spectrometer) is a commonly used elemental analysis instrument. It uses a plasma torch light source to excite the elements in the sample to produce characteristic spectra, and then uses an array solid detector to detect the intensity of these spectra to identify the type and content of the elements. In order to accurately measure the intensity of these spectra, it is necessary to control the opening and closing time of the mechanical shutter to control the exposure integration time of the array solid detector. As a key optical component in an ICP spectrometer, the mechanical shutter will open and close more slowly as the number of times the mechanical shutter is closed increases, due to the inherent fatigue characteristics of the material and the repeated action stress of the shutter blades, and its opening and closing delay time directly affects the accuracy of the exposure integration time, thereby affecting the measurement results of the element intensity.

[0003] Solutions of prior art: The methods for measuring mechanical shutter lag time in prior art mainly include a lighting control test method, which controls the light source device to emit light, sets an advance trigger time sequence, controls the camera to trigger the mechanical shutter multiple times to take pictures, and receives multiple test photos, which are compared with standard photos taken by a standard camera to determine the shutter lag time; a display switching test method, which sets the display element of the camera's display to a specific pattern, switches the state of the display element after a given time, executes the shutter operation synchronously with the switching action, captures the image of the display during the switching process, and derives the shutter lag based on the captured image.

[0004] Most existing technologies detect shutter lag time through camera imaging, but there are certain difficulties in detecting the lag time of the mechanical shutter used in the ICP spectrometer. First, the exposure time of the ICP spectrometer is often set in seconds, which is much longer than the mechanical shutter lag time. Therefore, it is difficult to measure the accurate millisecond-level lag time. In addition, there are certain difficulties in installation and disassembly. Secondly, the existing technology usually only records the shutter lag time and cannot fully evaluate the long-term stability and other performance of the mechanical shutter. Finally, the existing technology may be affected by ambient light when measuring the shutter lag time, thereby affecting the accuracy of the measurement results. Summary of the invention

[0005] To solve the above technical problems, the present invention provides a device and method for measuring the opening and closing lag time of a mechanical shutter of an ICP spectrometer, which is simple and easy to operate, improves the measurement efficiency, and ensures the accuracy and reliability of the measurement results.

[0006] The technical solution of the present invention is: a device for measuring the opening and closing lag time of a mechanical shutter of an ICP spectrometer, comprising a host computer, an FPGA circuit board, a light source, a mechanical shutter and a photosensitive diode, wherein the light source, the mechanical shutter and the photosensitive diode are sequentially arranged on the same horizontal line;

[0007] The host computer sends instructions to the FPGA circuit board, controls the opening and closing of the mechanical shutter through the FPGA circuit board to control the different exposure integration times of the photodiode, calculates the opening and closing hysteresis time of the mechanical shutter by collecting the light intensity signal received by the photodiode, and sends the opening and closing hysteresis time information of each time to the host computer.

[0008] Furthermore, it also includes a light source, which is a lighting lamp.

[0009] Furthermore, the photodiode is a silicon photodiode.

[0010] Furthermore, the FPGA circuit board is provided with a shutter control module and a collection module, the shutter control module is used to control the opening and closing of the mechanical shutter, and the collection module is used to collect signals from the photodiode.

[0011] The method for measuring the opening and closing lag time of a mechanical shutter of an ICP spectrum analyzer comprises the following steps:

[0012] Step 1: Prepare experimental equipment, including light source, mechanical shutter, photodiode and FPGA circuit board;

[0013] Step 2: Place the light source, mechanical shutter and photodiode on the same horizontal line and place the whole in a dark environment;

[0014] Step 3: Connect the mechanical shutter and the photodiode through the FPGA circuit board to control the opening and closing of the mechanical shutter and collect the light intensity signal received by the photodiode;

[0015] Step 4: Set the opening and closing times count of the mechanical shutter through the host computer software, and control the mechanical shutter to open and close repeatedly through the FPGA circuit board. The opening and closing times of the mechanical shutter are generally set to 1000 times.

[0016] Step 5: When the FPGA circuit board issues a command to open the mechanical shutter, the current opening time T of the mechanical shutter is recorded. a, compare the current collected by the photodiode with the current in the shutter open state, identify the open state according to the intensity, and record the mechanical shutter open time T′ when the collected current intensity reaches the set shutter fully open photodiode current threshold a , ΔT a =T′ a -T a This is the shutter opening time lag;

[0017] Step 6. Set the exposure time T and record the current time T when the exposure ends b , compare the current collected by the photodiode with the current in the shutter closed state, identify the closed state according to the intensity, and record the time T′ that the mechanical shutter has been opened when the collected current intensity reaches the photodiode current threshold set when the shutter is completely closed b , ΔT b =T′ b -T b It is the shutter closing time lag;

[0018] Step 7: The obtained ΔT a and ΔT b Send to the host computer for statistics.

[0019] Furthermore, in step 1, the light source is a lighting lamp, and the lighting level of the lighting lamp is higher than 5001x and lower than 50001x, and the mechanical shutter is a high-speed mechanical shutter.

[0020] Furthermore, in step 2, the illumination of the dark environment is lower than 0.1Ix.

[0021] Furthermore, in step 3, the FPGA circuit board is connected to the host computer through the network port, and the FPGA circuit board is provided with a shutter control module and an acquisition module, the shutter control module is used to control the opening and closing of the mechanical shutter, and the acquisition module is used to collect the signal of the photodiode.

[0022] Furthermore, step 8 is provided, wherein step 6 includes repeating steps 5, 6 and 7 for a total of 1000 times to obtain the statistical results of the opening and closing delay time of the mechanical shutter, and recording the maximum value of the opening and closing delay time of the mechanical shutter from the opening and closing delay time of a large amount of data: ΔT amax , ΔT bmax , minimum value: ΔT amin , ΔT bmin And the average: The calculation is as follows:

[0023] ΔT amax =Max(ΔT a ), ΔT bmax =Max(ΔTb )

[0024] ΔT amin =Min(ΔT a ), ΔT bmin =Min(ΔT b )

[0025]

[0026] The beneficial technical effects of the present invention are:

[0027] 1. Clearly control the exposure integration time: The present invention controls the opening and closing of the mechanical shutter through the FPGA circuit board, and collects the light signal passing through the mechanical shutter through the photodiode, so that the opening and closing state of the mechanical shutter can be accurately detected.

[0028] 2. Comprehensive evaluation of mechanical shutter performance: The present invention sets the opening and closing times of the mechanical shutter through the host computer software, and records the maximum, minimum and average values ​​of the mechanical shutter opening and closing delay time from a large amount of data, so as to comprehensively evaluate the performance of the mechanical shutter. This helps users understand the overall performance of the mechanical shutter and choose the appropriate product.

[0029] 3. Reduce the influence of ambient light: The present invention places the light source, mechanical shutter, and photodiode on the same horizontal line and places the whole in a dark environment, thereby reducing the influence of ambient light on the measurement results. This helps to improve the accuracy and reliability of the measurement results.

[0030] 4. Simplify the measurement process: The present invention records the opening and closing instructions issued by the FPGA circuit board T a and T b , the time when the mechanical shutter is fully opened T′ a and the time of complete closure T′ b , thus calculating the shutter opening time lag and shutter closing time lag. This measurement method is simple and easy to operate, and improves the measurement efficiency.

[0031] 5. Improve measurement accuracy: The present invention improves measurement accuracy by repeatedly measuring and recording the maximum, minimum and average values ​​of the mechanical shutter opening and closing delay time. This helps users to more accurately understand the performance of the mechanical shutter and thus select appropriate products to achieve a more accurate exposure integration time on the ICP spectrometer.

[0032] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0034] Figure 2 It is a schematic diagram of the detection process of the present invention. DETAILED DESCRIPTION

[0035] In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the specific implementation methods of the present invention are further described in detail below in conjunction with the drawings and examples. The following examples are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0036] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so as to describe the embodiments of the present application described herein.

[0037] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships described in the embodiments and shown in the accompanying drawings, or are directions or positional relationships in which the inventive product is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0038] like Figure 1 As shown, the present invention specifically relates to a device for measuring the opening and closing lag time of a mechanical shutter of an ICP spectrometer, comprising a host computer, an FPGA circuit board, a light source, a mechanical shutter and a photosensitive diode, and the light source, the mechanical shutter and the photosensitive diode are sequentially arranged on the same horizontal line;

[0039] The host computer sends instructions to the FPGA circuit board, controls the opening and closing of the mechanical shutter through the FPGA circuit board to control the different exposure integration times of the photodiode, calculates the opening and closing hysteresis time of the mechanical shutter by collecting the light intensity signal received by the photodiode, and sends the opening and closing hysteresis time information of each time to the host computer.

[0040] There are two modules on the FPGA circuit board: shutter control module and acquisition module. The shutter control module controls the opening and closing of the mechanical shutter. When the FPGA circuit board issues an opening command, the time T is recorded. 1, the mechanical shutter opens, the photodiode behind the mechanical shutter senses light and generates current, which is then converted into voltage. When compared with the voltage threshold when fully illuminated set on the FPGA circuit board, if it is greater than the threshold, the acquisition module transmits a rising edge to the FPGA circuit board, and the FPGA circuit board records the current time T 2 , the exposure time is set to T s , from T 1 Start counting T at the beginning s After that, the FPGA circuit board sends a command to close the shutter.

[0041] If the shutter is not fully opened, the light intensity received by the photosensitive diode at the rear will be weakened, and the induced current generated will also be reduced accordingly.

[0042] The integration time specifically refers to the time between the rising edge and the falling edge received by the FPGA circuit board to the acquisition module.

[0043] Rising edge: The photodiode receives the light signal transmitted by the opening of the mechanical shutter and generates an induced current. The induced current is converted into a voltage signal through the current voltage in the acquisition module. The voltage signal is compared with the initially set mechanical shutter opening voltage threshold. If it is higher than the threshold, a rising edge signal is generated and transmitted to the FPGA circuit board, proving that the shutter is open.

[0044] Falling edge: The photodiode receives the light signal transmitted by the mechanical shutter closing and generates an induced current. The induced current is converted into a voltage signal through the current voltage in the acquisition module. The voltage signal is compared with the initially set mechanical shutter closing voltage threshold. If it is lower than the threshold, a falling edge signal is generated and transmitted to the FPGA, proving that the shutter is closed.

[0045] Generally, the opening voltage threshold is set slightly lower than the voltage sensed by the photodiode when the mechanical shutter is fully opened; the closing voltage threshold is set slightly higher than the voltage sensed by the photodiode when the mechanical shutter is fully closed.

[0046] It also includes a light source, which is a lighting lamp.

[0047] The photodiode is a silicon photodiode.

[0048] The FPGA circuit board is provided with a shutter control module and a collection module. The shutter control module is used to control the opening and closing of the mechanical shutter, and the collection module is used to collect signals from the photodiode.

[0049] The method for measuring the opening and closing lag time of a mechanical shutter of an ICP spectrum analyzer comprises the following steps:

[0050] Step 1: Prepare experimental equipment, including light source, mechanical shutter, photodiode and FPGA circuit board;

[0051] In step 1, the light source is a lighting lamp, and the lighting level of the lighting lamp is higher than 5001x and lower than 50001x, and the mechanical shutter is a high-speed mechanical shutter.

[0052] Step 2: Place the FPGA circuit board, mechanical shutter and photodiode on the same horizontal line and place the whole in a dark environment;

[0053] In step 2, the illumination of the dark environment is less than 0.1Ix.

[0054] Step 3: Connect the mechanical shutter and the photodiode through the FPGA circuit board to control the opening and closing of the mechanical shutter and collect the light intensity signal received by the photodiode;

[0055] In step 3, the FPGA circuit board is connected to the host computer through the network port, and the FPGA circuit board is provided with a shutter control module and an acquisition module, the shutter control module is used to control the opening and closing of the mechanical shutter, and the acquisition module is used to collect the signal of the photodiode.

[0056] Step 4: Set the opening and closing times count of the mechanical shutter through the host computer software, and control the mechanical shutter to open and close repeatedly through the FPGA circuit board. The opening and closing times of the mechanical shutter are generally set to 1000 times.

[0057] Step 5: When the FPGA circuit board issues a command to open the mechanical shutter, the current opening time T of the mechanical shutter is recorded. a , compare the current collected by the photodiode with the current in the shutter open state, identify the open state according to the intensity, and record the time T′ that the mechanical shutter has been open when the collected current intensity reaches the peak value a , ΔT a =T′ a -T a This is the shutter opening time lag;

[0058] The circuit board is connected to the host computer and records the time T when the host computer issues an order to open the mechanical shutter. a As the mechanical shutter is fully opened, the light intensity collected by the photodiode reaches saturation. By comparing the current collected by the photodiode when the shutter is fully opened, the open state is identified. When the collected current intensity reaches the peak value, the comparator outputs a signal to the main control chip to record the time T′ that the mechanical shutter has been opened. a , T′ a -T a This is the shutter opening time lag.

[0059] Step 6. Set the exposure time T and record the current time T when the exposure ends b, compare the current collected by the photodiode with the current in the shutter closed state, identify the closed state according to the intensity, and record the time T′ that the mechanical shutter has been open when the collected current intensity reaches the valley value b , ΔT b =T′ b -T b It is the shutter closing time lag;

[0060] Set the exposure time T and record the current time T when the exposure ends b As the mechanical shutter is completely closed, the light intensity collected by the photodiode reaches a valley value. By comparing it with the current collected by the photodiode when the shutter is fully closed, the closed state is identified. The closed state is identified based on the current intensity. When the collected current intensity reaches the valley value, the time T′ that the mechanical shutter has been open is recorded. b , T′ b -T b This is the shutter closing time lag. This setting can accurately measure the mechanical shutter time lag.

[0061] The exposure time refers to the time between the opening and closing of the mechanical shutter.

[0062] Step 7: The obtained ΔT a and ΔT b Send to the host computer for statistics.

[0063] There is also a step 8, wherein the step 6 includes repeating the steps 5, 6 and 7 for a total of 1000 times to obtain the statistical results of the opening and closing delay time of the mechanical shutter, and recording the maximum value of the opening and closing delay time of the mechanical shutter from the opening and closing delay time of a large amount of data: ΔT amax , ΔT bmax , minimum value: ΔT amin , ΔT bmin And the average: The calculation is as follows:

[0064] ΔT amax =Max(ΔT a ), ΔT bmax =Max(ΔT b )

[0065] ΔT amin =Min(ΔT a ), ΔT bmin =Min(ΔT b )

[0066]

[0067] The above embodiments are only specific implementation methods of the present invention, which are used to illustrate the technical solutions of the present invention rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the aforementioned embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the aforementioned embodiments within the technical scope disclosed by the present invention, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the protection scope of the present invention.

Claims

1. A device for measuring the opening and closing lag time of a mechanical shutter of an ICP spectrometer, characterized in that: It includes a host computer, an FPGA circuit board, a light source, a mechanical shutter and a photosensitive diode, and the light source, the mechanical shutter and the photosensitive diode are arranged in sequence on the same horizontal line; The mechanical shutter and the photodiode are both located in the dark environment tooling; The host computer sends instructions to the FPGA circuit board, controls the opening and closing of the mechanical shutter through the FPGA circuit board to control the different exposure integration times of the photodiode, calculates the opening and closing hysteresis time of the mechanical shutter by collecting the light intensity signal received by the photodiode, and sends the opening and closing hysteresis time information of each time to the host computer.

2. The device for measuring the opening and closing lag time of the mechanical shutter of an ICP spectrometer according to claim 1, characterized in that: It also includes a light source, which is a lighting lamp.

3. The device for measuring the opening and closing lag time of the mechanical shutter of an ICP spectrometer according to claim 1, characterized in that: The photodiode is a silicon photodiode.

4. The device for measuring the opening and closing time lag of the mechanical shutter of an ICP spectrometer according to claim 1, characterized in that: The FPGA circuit board is provided with a shutter control module and a collection module. The shutter control module is used to control the opening and closing of the mechanical shutter, and the collection module is used to collect signals from the photodiode.

5. The method for measuring the opening and closing lag time of the mechanical shutter of an ICP spectrometer according to claim 1 is characterized in that: The following steps are involved: Step 1: Prepare experimental equipment, including light source, mechanical shutter, photodiode and FPGA circuit board; Step 2: Place the light source, mechanical shutter and photodiode on the same horizontal line and place the whole in a dark environment; Step 3: Connect the mechanical shutter and the photodiode through the FPGA circuit board to control the opening and closing of the mechanical shutter and collect the light intensity signal received by the photodiode; Step 4: Set the opening and closing times count of the mechanical shutter through the host computer software, and control the mechanical shutter to open and close repeatedly through the FPGA circuit board. The opening and closing times of the mechanical shutter are generally set to 1000 times. Step 5: When the FPGA circuit board issues a command to open the mechanical shutter, the current opening time T of the mechanical shutter is recorded. a , compare the current collected by the photodiode with the current in the shutter open state, identify the open state according to the intensity, and record the time T′ that the mechanical shutter has been open when the collected current intensity reaches the peak value a , ΔT a =T′ a -T a This is the shutter opening time lag; Step 6. Set the exposure time T and record the current time T when the exposure ends b , compare the current collected by the photodiode with the current in the shutter closed state, identify the closed state according to the intensity, and record the time T′ that the mechanical shutter has been open when the collected current intensity reaches the valley value b , ΔT b =T′ b -T b It is the shutter closing time lag; Step 7: The obtained ΔT a and ΔT b Send to the host computer for statistics.

6. The method for measuring the opening and closing lag time of the mechanical shutter of an ICP spectrometer according to claim 5, characterized in that: In step 1, the light source is a lighting lamp, and the lighting level of the lighting lamp is higher than 5001x and lower than 50001x, and the mechanical shutter is a high-speed mechanical shutter.

7. The method for measuring the opening and closing lag time of the mechanical shutter of an ICP spectrometer according to claim 5, characterized in that: In step 2, the illumination of the dark environment is less than 0.1 lx.

8. The method for measuring the opening and closing lag time of the mechanical shutter of an ICP spectrometer according to claim 5, characterized in that: In step 3, the FPGA circuit board is connected to the host computer through the network port, and the FPGA circuit board is provided with a shutter control module and an acquisition module, the shutter control module is used to control the opening and closing of the mechanical shutter, and the acquisition module is used to collect the signal of the photodiode.

9. The method for measuring the opening and closing lag time of the mechanical shutter of an ICP spectrometer according to claim 5, characterized in that: There is also a step 8, wherein the step 6 includes repeating the steps 5, 6 and 7 for a total of 1000 times to obtain the statistical results of the opening and closing delay time of the mechanical shutter, and recording the maximum value of the opening and closing delay time of the mechanical shutter from the opening and closing delay time of a large amount of data: ΔT amax , ΔT bmax , minimum value: ΔT amin , ΔT bmin And the average: The calculation is as follows: ΔT amax =Max(ΔT a )、ΔT bmax =Max(ΔT b ) ΔT amin =Min(ΔT a )、ΔT bmin =Min(ΔT b )

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