JPH09318544A - Method and equipment for analyzing specimen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and a method for analyzing a specimen through simple arrangement in which an optical unit is shifted accurately relative to a test paper in order to analyze the specimen with high accuracy. SOLUTION: A test paper 15 is irradiated, at an inspecting position, with light from the emitting section of an optical unit 32. The optical unit 32 receives the reflected light at the light receiving section thereof while moving relatively along the test paper 15. First and second reference reflecting sections 30a, 19a are disposed, respectively, at the inspecting position and for the test paper 15. Before each test piece 18 is tested, a control means shifts the optical unit 32 relatively from the first reference reflecting section 30a at the inspecting position to the second reference reflecting section 19a of the test paper 15. The second reference reflecting section 19a is detected based on the quantity of reference light reflected from the first reference reflecting section 30a. The distance from the second reference reflecting section 19a to each test piece 18 is calculated based on the difference in the quantity of reflected light from each test piece 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sample analyzer and a sample analysis method, and more particularly to a sample analyzer capable of accurately moving an optical device relative to a test strip in order to enable highly accurate sample analysis. And a sample analysis method.

[0002]

2. Description of the Related Art Conventionally, a test paper has been used for examining a sample such as urine. This test paper is obtained by adhering a plurality of test pieces containing different reagents to a strip-shaped support at predetermined intervals along the longitudinal direction.

In the sample analysis using such a test paper, the color reaction of each test piece is automatically measured by the reflection photometric method. That is, each test piece is irradiated from the light emitting section of the optical device, and the reflected light is received by the light receiving section.

[0004]

However, in the conventional sample analysis, since the test paper was set by hand, the position of the test paper was not accurate, and the position of each test piece could not be detected accurately. There is a problem that desired detection accuracy cannot be obtained.

The positions of the test pieces are deviated due to manufacturing errors. Therefore, it is necessary to accurately detect the position of each test piece in advance before measuring the color reaction.

As the urine analyzer capable of detecting the position of each test piece as described above, for example, the following has been proposed (see, for example, Japanese Patent Publication No. 6-43996). That is, in this urine analyzer, the optical device is moved from one end to the other end of the test paper before the detection of the color reaction in each test piece, so that the peak value of the sawtooth-shaped reflected light amount is detected. The position of each test piece is specified based on this, and the distance from the microswitch is calculated by turning on the microswitch at a predetermined position. Further, before the color reaction is detected, the amount of light emitted from the light emitting element is corrected by comparing the amount of reflected light obtained at the home position with a preset reference value.

However, the urine analyzer requires a micro switch for stopping the movement of the optical device in addition to the home position for correcting the light emission amount of the light emitting element, which is costly. Further, since the distance between each test piece and the microswitch is calculated based on the elapsed time from the time when the optical device detects each position, it is necessary to keep the moving speed of the optical device constant. is there. Therefore, even when there are few inspection items, the time required for the inspection is the same.

In view of the above, the present invention provides a sample analyzer and a sample analysis method having a simple structure in which an optical device can be accurately moved relative to a test paper in order to perform a highly accurate sample analysis. It is an issue.

[0009]

In order to achieve the above object, according to the present invention, an optical device is relatively moved along a test sheet arranged at an inspection position, and each test provided from the light emitting portion of the optical device to the test sheet. In the sample analyzer, which sequentially irradiates the test pieces, receives the reflected light at the light receiving part of the optical device, and measures the reflected light amount to analyze the sample impregnated in each of the test pieces. Before the sample analysis on the first reference reflecting portion formed on the test paper and the second reference reflecting portion formed on the test paper among the positions, the optical device is used for inspection. And a control means for identifying the arrangement position of the test paper by detecting the reference reflection light quantity of the second reference reflection portion of the test paper based on the reference reflection light quantity detected by the first reference reflection portion of the position. Is. In the relative movement of the test paper and the optical device, only the test paper is moved, only the optical device is moved, or
Any means for moving both may be adopted.

It is preferable that the control means calculates the distance from the second reference reflecting portion to each test piece based on the difference in the amount of reflected light on each test piece. In the sample analysis, it is more preferable that the optical device is sequentially stopped at a position facing each test piece.

In order to achieve the above object, according to the present invention, the optical device is relatively moved along the test paper arranged at the inspection position, and the test pieces provided on the test paper are sequentially irradiated from the light emitting portion of the optical device. Then, the reflected light is received by the light receiving part of the optical device,
By measuring the amount of the reflected light, in the sample analyzer for analyzing the sample impregnated in each of the test pieces, a reference reflecting portion formed at a position where the test paper is not arranged among the inspection positions, Based on the amount of light reflected by the reference reflector, the light receiver adjusts the gain and the offset, and when the gain and offset deviate from the preset gain and offset widths, a control means for notifying an error is provided.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a plan view of a urine analyzer which is an example of a sample analyzer according to the present invention, and FIG. 2 (a) is a side view thereof. This urine analyzer includes a device body 1, a test tube holder 2, a urine amount detector 3, a test paper container 4 (see FIG. 2),
A handling section 5 (see FIG. 2), a color reaction section 6 and a control device 7 (see FIG. 5) for controlling the operations of these are provided.

The test tube holding portion 2 is formed by forming notches 11 for holding the test tube 10 in a turntable 9 rotated by a motor 8 in two rows of inner and outer circumferences. A servomotor or the like can be used as the motor 8 and can be rotated by a predetermined pitch so that each test tube 10 can be sequentially moved to a predetermined position.

The urine amount detecting section 3 is a conventionally well-known one in which two electrodes 14a and 14b are arranged side by side at a predetermined interval via an electrode holding section 13 at the tip of an arm 12 which moves in parallel in the vertical and horizontal directions. (See, for example, JP-A-61-191571). The urine amount detection unit 3 includes both electrodes 14a and 14b.
When is inserted into the test tube 10, the liquid amount is detected by the presence or absence of conduction.

The test strip accommodating portion 4 includes a cassette 16 accommodating a plurality of test strips 15 and a base plate 17 provided on the bottom surface thereof.
It is composed of The base plate 17 can reciprocate in the width direction on the bottom surface of the cassette 16. Further, the base plate 17 is formed with a groove 20 capable of accommodating only one test paper 15. Then, by slidingly moving, only one test paper 15 stored in the cassette 16 can be held in the groove portion 20 and discharged to the outside. The test strip accommodating section 4 is attached to the apparatus main body 1 in an inclined manner. As a result, the test paper 15 taken out by the base plate 17 slides on the inclined surface and the rear ends are aligned, so that the front ends are always at the same position.
Therefore, it can be reliably held by the handling unit 5 described below.

The test paper 15 contained in the cassette 16
The test piece 18 is attached to the support 15a such as a PET (polyethylene terephthalate) film at a predetermined interval from the one end side, and the other end is used as the grip portion 19. Each test piece 18 contains various reagents so that glucose, protein, etc., which are urinary components, can be detected. However, the test piece 18a on the one end side does not contain anything, and is a test piece that serves as a reference for the amount of reflected light in the other test pieces 18. Further, a black marker 19a (corresponding to the second reference reflecting portion of the present invention) is painted on the grip portion 19.
The black marker 19a can be easily formed in the same step as the sticking of the test pieces 18, and serves as a reference position for measuring the distance to each test piece 18.

As shown in FIG. 2A, the handling section 5 is composed of a vertical plate 21, a slide plate 22, an elevating plate 23 and a holding section 24. The vertical plate 21 is fixed to the apparatus main body 1, and one surface of the vertical plate 21 is provided with rails 25 in the upper and lower two rows in the horizontal direction.
have. The slide plate 22 is horizontally reciprocally movable along the rail 25 of the vertical plate 21, and has a rail 26 extending in the vertical direction. The lift plate 23 can reciprocate in the vertical direction along the rail 26 of the slide plate 22. The holding portion 24 has a support shaft 24 at the tip of the lift plate 23.
It is provided so as to be rotatable about a and is rotated in a vertical plane by driving a motor 27 provided at the rear end of the elevating plate 23. The sandwiching portion 24 includes a pair of upper and lower sandwiching pieces 28.
The test paper 15 can be pinched.

The color reaction section 6 comprises a test paper setting section 29, a carrying table 30, a carrying section 31, and an optical device 32.

As shown in FIG. 2 (b), the test paper setting section 29 includes an excess urine suction table 33 having guide grooves 34 formed in the front-rear direction on the apparatus main body 1 along a guide rail 39. It is designed to slide. The guide groove 34 of the excess urine suction table 33 is formed in a step shape, the test paper 15 is placed on the upper side thereof, and the excess urine flows down to the lower side. Suction holes 35 are formed at two locations on the bottom surface of the guide groove 34, and communicate with a drain bottle 37 via a discharge path 36. Then, by driving the air pump 38, excess urine attached to the test paper 15 can be sucked into the drain bottle 37 through the suction hole 35. The excess urine suction table 33 is adapted to be moved forward to a position where test paper can be easily set by a manual operation described below.

The carrying table 30 is arranged on the side of the test paper setting section 29, and a plurality of ridges 40 are formed on the upper surface thereof at predetermined intervals along the carrying direction. These ridges 40 reduce the contact area with the surface of the transport table 30 when the test paper 15 is placed, minimize the adhesion of urine, and promote the drying of the test paper 15. Is playing. Further, recesses 41 are formed at predetermined intervals on the ridges 40, and constitute three relay positions A for stably mounting the test paper 15 conveyed by the conveyor 31. A white plate 30a is provided on the rear end side of the apparatus body 1 at the edge of the transport table 30 (the position where the optical device 32 described below reciprocates). The white plate 30a (corresponding to the first reference reflecting portion of the present invention) is used for gain adjustment and offset adjustment described below, and also the optical device 32.
It is also used when calculating the positional relationship between each of the test pieces 18 of the test paper 15.

The carrying section 31 is the handling section 5
It has a pair of upper and lower sandwiching pieces 42 similar to the above, and can reciprocate the side edge of the transport table 30 along the guide rail 43. The holding piece 42 is configured to be capable of lifting and holding the test paper 15 placed on the test paper setting unit 29 or the transport table 30 by rotating downward.

The optical device 32 includes a light emitting section 44 and a light receiving section 45. A plurality of LEDs are used for the light emitting unit 44, and the control device 7 controls the D / A converter 47 and the driving circuit 4
Light having a predetermined wavelength is sequentially emitted at predetermined intervals based on a signal input via 6. A plurality of photodiodes are used for the light receiving section 45, and the light emitted from the light emitting section 44 and reflected by the transport table 30 or the test paper 15 is received and converted into a digital signal via the amplifier 48 and the A / D converter 49. It is output to the control device 7 (see FIG. 5). Light receiving part 4
The reason why a plurality of photodiodes are used in 5 is to enable more appropriate detection from the average value of the amount of light detected by each photodiode. Further, the optical device 32 reciprocates along the longitudinal direction of the conveyed test paper 15. A pulse motor 50 is used for this movement. That is, a pinion (not shown) provided on the rotation shaft of the pulse motor 50 and a rack (not shown) provided along the front-rear direction of the transport table 30 are meshed with each other, so that a predetermined number of input pulses is obtained. It is possible to move pitch by pitch.

As shown in FIG. 5, the control unit 7 receives signals from the manual switch 51, the urine volume detection unit 3, and the optical device 32, and receives the motor 8 of the test tube holding unit 2, the urine volume detection unit 3, and the test. A control signal is issued to the paper storage unit 4, the handling unit 5, the color reaction unit 6, and the display unit 52.

The urine analysis process in the control device 7 of the urine analyzer will be described with reference to the flowcharts of FIGS.

First, by sliding the base plate 17 of the test paper container 4, one test paper 15 is taken out,
By driving the handling unit 5, the holding unit 2
It is gripped at 4 (step S1). On the other hand, the amount of urine in the test tube 10 to be analyzed is a set value (for example, 9
cc) is exceeded (step S2).
The amount of urine is detected by driving the urine amount detector 3 and inserting the electrodes 14a and 14b held at the tip of the arm 12 to a predetermined position in the test tube 10 and determining whether or not there is conduction between the electrodes 14a and 14b. . When the amount of urine is small and there is no conduction between the electrodes 14a and 14b, it is determined that the amount of urine does not exceed the set value. In this case, the urine analyzer cannot automatically perform urine analysis. Therefore, the number (port number) of the corresponding test tube 10 is stored (step S3), and the next test tube 10 is set by rotating the turntable 9 (step S4).

When there is conduction between the electrodes 14a and 14b,
Since it is determined that the amount of urine exceeds the set value, the urine analyzer can automatically perform urine analysis. Therefore, the handling section 5 is driven to insert the test strip 15 into the test tube 10 to dip urine (step S).
5). When the dipping is completed, the handling section 5 is driven again, and the test paper 15 is pulled up from the test tube 10,
Next, set it on the surplus urine suction table 33 (step S
6). Then, by driving the air pump 38,
Excess urine is discharged to the drain bottle 37 through the suction hole 35 (step S7). As a result, it is possible to avoid a problem in which the excess urine remains and adheres to the next test strip 15 to prevent proper analysis.

Next, the test paper 15 after removing the excess urine is conveyed (step S8). The test paper 15 is transported by the transport unit 31
Is driven to one of the relay positions A on the transport table 30, and after at least waiting for a sufficient time (reaction time) for the color reaction, it is transported to the optical device 32. Even while the test paper 15 is waiting at the relay position A, the next test paper 15 is sequentially transported to another relay position A by the driving of the transport unit 31. Then, among the test papers 15 transported to the relay position A, the ones after the reaction time has passed are sequentially transported to the photometric portion below the optical device 32.

Subsequently, after the urine analysis process described below is performed by the optical device 32 (step S9), the test paper 15 is discarded (step S10).

The urine analysis process is performed according to the flowchart of FIG. That is, from the light emitting unit 44 to the transport table 30.
The white plate 30a provided above is sequentially irradiated at a predetermined interval, and the reflected light is received by the light receiving section 45. Then, the gain adjustment and the offset adjustment of the amplifier 48 are performed based on the received light amount (step S21). However, the optical device 3
2 is not in a position facing the white plate 30a, the device body 1
By moving the white plate 30a to the rear side, the white plate 30a is stopped at the detected position.

The gain adjustment is performed by averaging a plurality of wavelengths received by the light receiving section 45 and calculating the gain so as to obtain a target A / D value. The average value of the wavelengths is obtained by a value after the output of the amplifier 48 is stable, that is, after a lapse of a predetermined time from the input of the reflected light. The offset adjustment is performed by obtaining the offset amount so that the output of the amplifier 48 is minimized when the light emitting unit 44 is turned off, and correcting the gain obtained by the gain adjustment based on the offset amount. When the calculated gain or the adjusted offset amount does not fall within the gain width or the offset width determined by the experiment in advance, it is determined that the adjustment trouble occurs, the fact is displayed on the display unit 52, and the operator is notified by sound. The cause of the poor gain adjustment is, for example, that the amount of light emitted from the light emitting section 44 is not appropriate or that the white plate 30a is dirty. Further, as a cause of the offset adjustment failure, there is a case where light from another light source enters.

After gain adjustment and offset adjustment,
Next, the optical device 32 is attached to the device main body 1 as shown in FIG.
To the front side (step S22). The moving speed is gradually increased from the start of the movement, and is kept constant before reaching the test paper 15. During this period, irradiation from the light emitting unit 44 is continued, and as shown in FIG. 4B, a digital signal corresponding to the amount of light received by the light receiving unit 45 is stored (step S
23). Then, it is determined whether or not the black marker 19a is detected (step S24). The black marker 19a is the white plate 3
The wavelength of the reflected light at 0a is used as a reference value, and the amount of reflected light becomes, for example, ¼ or less of this reference value, and detection is performed.
However, instead of the black marker 19a, a through hole may be provided at that position, and the carrier table 30 may be black, so that the reflected light may be detected. Anything can be detected. As a result, the position of the black marker 19a, which is the second reference reflecting portion, can be detected accurately at high speed.

When the black marker 19a is detected, the black marker 19a is gradually decelerated and stopped at the time point when it advances by 4.5 mm (step S2).
5). Then, each test piece 1 stored as described above
The distance from the black marker 19a to each test piece 18 is calculated based on the data indicating the position 8 (step S26).
Here, a pulse motor 50 that moves the optical device 32 is used.
Calculate the number of oscillation pulses to. Then, the pulse motor 5
The optical device 32 is moved to the back side by driving 0, and is stopped once when the black marker 19a is crossed. Next, the distance between the optical device 32 and the test piece 18a is calculated from the distance between the optical device 32 and the black marker 19a and the distance between the black marker 19a and the test piece 18a (containing no reagent), and the optical device is calculated. 32 is moved to a position facing the test piece 18a. Then, after waiting until the aftershock of the optical device 32 (meaning vibration until completely stopped) is stopped, the amount of reflected light is measured (step S27). This is test piece 1
This is because the amount of reflected light at 8a is used as a reference value and the amount of reflected light at another test piece 18 is corrected. That is, by comparing the reference value with the reflected light amount (experimental reference value) of the test piece 18a detected in advance by an experiment, each reflected light amount (experimental value) of the other test piece 18 is corrected by the difference. To do.
Similarly, the optical device 32 is made to face each test piece 18, and the amount of reflected light (measured value) at each test piece 18 containing a reagent is sequentially compared with each of the correction values, and the urine analysis is performed based on the deviation amount. I do.

As described above, in the optical device 32, the white plate 30a
Since the amount of reflected light at the black marker 19a is detected based on the amount of reflected light at, the position can be reliably detected due to the remarkable difference in the amount of reflected light. Further, since the distance from the black marker 19a to each test piece 18 is also detected based on the amount of light reflected by each test piece 18, even if the position of the test piece 18 is displaced due to a manufacturing error, the optical device It is possible to move 32 to an appropriate position.
Further, in the urine analysis, the optical device 32 is used for each test piece 18
Therefore, the distance between the optical device 32 and the test piece 18 does not fluctuate due to vibration and noise is not superimposed on the signal, and the SN ratio is improved (especially noise (N (N ) Decreases). Therefore, highly accurate urine analysis is possible.

It should be noted that, if the threshold value (a value smaller than the minimum value of the amount of reflected light on each test piece 18 is set as the threshold value) is not exceeded by the light emission and the light reception, it is determined that there is no test paper. If the threshold value is once exceeded, but if it does not exceed the threshold value after that, the operator is notified in the same manner as described above, assuming that an abnormality has occurred in the detection of the black marker 19a.

After that, it is judged whether or not a series of urine analysis processing (50 ports in this embodiment) is completed (step S11). If not completed, the above-mentioned steps S1 to S1.
Repeat 0.

If the series of urine analysis is completed, it is judged whether or not the urine analysis is to be performed by manual measurement for the test tube 10 in which the amount of urine was too small to be automatically analyzed (step S12). This determination is made based on whether or not the input from the manual switch 51 is within a predetermined time. When the manual operation is not performed, the urine analysis process ends.

On the other hand, when the manual operation is performed, the port number of the test tube 10 which could not be automatically analyzed is displayed on the display unit 52 (step S13), and the turntable 9 is rotated (step S14) to set the test paper. The part 29 is advanced to a position where the test paper 15 can be easily set (step S15). At this point, each test piece 18 of the test paper 15 is waited for a time (about 5 seconds) which is considered to be sufficient for dipping urine, and a confirmation sound of "beep" is generated. Furthermore, the time (about 7 seconds) considered to be sufficient for setting the test paper 15 in the test paper setting unit 29.
Just wait and make a beep sound. Then, the test strip setting unit 29 is moved back to the original position (step S16), and the presence or absence of the test strip 15 is once detected by a sensor (not shown). When the test paper 15 is detected, the test paper 15 is transported (step S17), urine analysis processing is performed (step S18), and the test paper 15 is discarded (step S19), as in steps S8 to S10. The steps S13 to S19 are repeated until it is determined in step S12 that the manual measurement is not performed.

In steps S15 and S16,
Although the test strip setting unit 29 is automatically moved forward / backward according to the elapsed time, a touch panel may be adopted as the display unit 52 to sequentially display the operation procedure on the screen. That is, characters such as "manual operation", "analysis processing", "analysis processing start", etc. may be sequentially displayed. According to this, the operator only has to directly push the screens in accordance with the display of the display unit 52, and the operation can be performed easily and smoothly.

Further, the inspection item on each of the test papers 15 may be freely changed, and in that case, the width of the black marker 19a may be changed for each test paper 15 having a different inspection item.
For example, when the inspection item differs depending on the sample, the optical device 3
If the width dimension of the black marker 19a is detected in 2 and the movement position of the optical device 32 is automatically determined from the difference in the width dimension, the urine analysis process can be performed at a higher speed.

In the above embodiment, the urine analyzer is described as the sample analyzer, but the sample analyzer is also applicable to other sample analyzers such as when analyzing blood (serum, plasma, etc.). .

Further, in the above embodiment, each test piece 18
The center position of the test piece 18 is specified based on the amount of reflected light, but if the detection accuracy is not so high, the position of each test piece 18 is assumed to be constant, and the black marker input in advance is used. The drive of the optical device 32 may be controlled based on the distance from 19a to each test piece 18, or the optical device 32 does not have to be stopped for each test piece 18.
You may make it move at a constant speed.

[0043]

As is apparent from the above description, according to the sample analyzer or the sample analysis method of the present invention, it is possible to obtain the reference reflected light amount at the inspection position and the test paper.
And the second reference reflecting portion are provided respectively,
It is possible to accurately detect the arrangement position of the test strip.
Therefore, the optical device can be accurately opposed to the desired position of each test piece based on the distance from the second reference reflecting portion provided on the test paper to each test piece, and the detection accuracy can be improved.

Further, since the position of each test piece is specified based on the amount of light reflected by each reference reflecting portion and the test piece, even if the position of the test piece is deviated due to manufacturing error or the like,
It is possible to accurately irradiate each test piece and receive the reflected light thereof, and it is possible to further improve the detection accuracy. In this case, the second reference reflecting portion can be formed on the test paper in the same manner as the test piece, so that the second reference reflecting portion can be easily manufactured, and the conventional micro switch or the like is unnecessary, and the cost can be reduced. It is possible.

Further, since the optical device is sequentially stopped at the position opposed to each test piece to perform the sample analysis, the influence of noise and the like due to the vibration can be eliminated and the detection accuracy can be improved.

Further, since the gain adjustment and the offset adjustment in the light receiving portion are performed based on the amount of light reflected by the reference reflecting portion provided at the inspection position, accurate measurement can always be performed. Also, when a value outside the preset range is detected, an error can be notified, so
Repairs can be done before a failure occurs.

[Brief description of drawings]

FIG. 1 is a plan view of a urine analyzer which is an example of a sample analyzer according to the present invention.

FIG. 2 is a side view (a) of FIG. 1 and a perspective view (b) showing an excess urine suction table and a test strip.

FIG. 3 is an enlarged plan view of the transport table of FIG.

FIG. 4 is a cross-sectional view (a) showing the positional relationship between the optical device and the test paper, and a graph (b) showing the amount of reflected light on each test piece.

5 is a block diagram showing an input / output relationship of signals to / from the control device of FIG.

6 is a flowchart showing a urine analysis process performed by the control device of FIG.

FIG. 7 is a flowchart showing a urine analysis process performed by the control device of FIG.

8 is a flowchart showing a urine analysis process performed by the control device of FIG.

[Explanation of symbols]

 15 test paper 18 test piece 19a black marker (second reference reflecting portion) 30a white plate (first reference reflecting portion) 32 optical device 44 light emitting portion 45 light receiving portion

Claims (8)

[Claims] 1. An optical device is relatively moved along a test paper arranged at an inspection position, and each test piece provided on the test paper is sequentially irradiated with light from a light emitting portion of the optical device, and reflected light is reflected by a light receiving portion of the optical device. In a sample analyzer configured to analyze the sample impregnated in each of the test pieces by receiving the light and measuring the amount of reflected light, a first reference formed at a position of the inspection position where no test paper is arranged. A reflection part, a second reference reflection part formed on the test paper, and a reference reflection light amount detected by the first reference reflection part at the inspection position in the optical device before the sample analysis in each test piece. And a control means for identifying the arrangement position of the test paper by detecting the amount of reference reflected light at the second reference reflecting portion of the test paper. 2. The control means calculates the distance from the second reference reflecting portion to each test piece based on the difference in the amount of reflected light on each test piece. The sample analyzer according to. 3. The controller according to claim 1 or 2, wherein the control device sequentially stops the optical device at a position facing each test strip in the sample analysis of each of the test strips. Sample analyzer. 4. An optical device is relatively moved along a test sheet arranged at an inspection position, and each test piece provided on the test sheet is sequentially irradiated with light from a light emitting portion of the optical device, and reflected light is reflected by a light receiving portion of the optical device. In the sample analyzer which receives the light and measures the amount of reflected light to analyze the sample impregnated in each of the test pieces, a reference reflecting part formed at a position where the test paper is not arranged among the inspection positions. And a control means for performing gain adjustment and offset adjustment in the light receiving unit based on the amount of light reflected by the reference reflecting unit and notifying an error when the gain and offset widths deviate from the preset gain width and offset width. Characteristic sample analyzer. 5. A sample analysis method for analyzing and processing a sample impregnated in each test piece by sequentially irradiating each test piece of a test strip arranged at the inspection position and receiving the reflected light thereof, wherein While the test paper is not arranged and the test paper is provided with the first and second reference reflecting portions capable of obtaining the reference reflected light amount, respectively, the first reference reflecting portion is provided before the sample analysis of each test piece. A sample analysis method, characterized in that the second reference reflecting portion is detected on the basis of the amount of reflected light obtained by irradiating the sample, and the arrangement position of the test paper is specified. 6. The sample analysis method according to claim 5, wherein the distance from the second reference reflecting portion to each test piece is calculated based on the difference in the amount of reflected light on each test piece. 7. The sample analysis method according to claim 5, wherein in the sample analysis of each of the test strips, the optical device is sequentially stopped at a position facing each of the test strips. 8. A sample analysis method for analyzing and processing a sample impregnated in each test piece by sequentially irradiating each test piece of a test strip arranged at the inspection position and receiving the reflected light thereof. Based on the amount of light reflected by the reference reflector formed at the position where the test paper is not arranged, the gain adjustment and the offset adjustment are performed in the light receiving unit, and if the gain width and the offset width are out of the preset range, an error is notified. A sample analysis method characterized by the above.