Patent Publication Number: US-2012038913-A1

Title: Optical measurement instrument equipped with transportation protection

Description:
FIELD OF THE INVENTION 
     The invention relates to an arrangement and a method for equipping an optical measurement instrument with transportation protection. Furthermore, the invention relates to an optical measurement instrument equipped with transportation protection. 
     BACKGROUND 
     The work in analytical biochemical laboratories and in clinical laboratories is often based on different optical measurements, which can be, for example but not necessarily, absorption measurements, photoluminescence measurements, and/or chemiluminescence measurements. Further, there is an analysing method called Amplified Luminescent Proximity Homogeneous Assay or AlphaScreen™. 
       FIG. 1   a  shows a schematic illustration of a known optical measurement instrument suitable for performing some or all of the measurements of the kind mentioned above.  FIG. 1   b  shows schematic illustration of a view seen downwards from line A-A of  FIG. 1   a . Samples  151 ,  152 ,  153 ,  154 ,  155 ,  156 ,  157  to be measured are stored in sample wells that are built on a sample plate  120  e.g. a microtitration plate. The optical measurement instrument includes an excitation light source  121  arranged to produce an excitation beam. The excitation light source can be for example a laser source or a flash lamp such as a xenon flash lamp. The excitation beam is focused to a light guide  122  that can be e.g. a fiber bundle. The light guide  122  is connected to an optical module  123  that constitutes an optical interface arranged to direct the excitation beam to the sample  153  to be measured and/or to collect an emission beam from the sample to be measured. The emission beam is conducted via a light guide  124  to a detector  125  arranged to detect the emission beam and to produce a detection signal responsive to the detected emission beam. The detector can be for example a photodiode or a photomultiplier tube. 
     The optical measurement instrument includes a mechanical support element  102  onto which the optical module  123  constituting the optical interface can be fastened. The mechanical support element  102  is connected to a body structure  101  of the optical measurement instrument with the aid of threaded rods  103  and  104  and counterparts  105  and  106  so as to allow the distance D from the optical interface to the measured and/or excited sample  153  to be adjusted. The counterparts  105  and  106  may include, for example, servomotors arranged to move the mechanical support element  102  in the positive or negative z-direction of a co-ordinate system  190  in order to adjust the distance D. 
     The optical measurement instrument includes a receptable element  111  that is suitable for receiving the sample plate  120 . The optical measurement instrument includes mechanical support elements arranged to moveably support the receptable element  111  with respect to the body structure  101 . These mechanical support elements include a support rail  108  and guide elements  109  and  110  shown in  FIG. 1   b . The support rail  108  is supported relative to the body structure  101  with the aid of the guide elements  109  and  110  in such a manner that the support rail is movable in the directions of a two-headed arrow  126  shown in  FIG. 1   b . The receptable element  111  is connected with the aid of a part  107  to the support rail  108  in such a manner that the receptable element is capable of sliding along the support rail in the longitudinal direction of the support rail, i.e. the receptable element is movable in the directions of a two-headed arrow  127  shown in  FIG. 1   b . Hence, the samples stored in the sample wells of the sample plate  120  are movable in the xy-plane defined by the co-ordinate system  190 . Due to the fact that the samples are movable in the xy-plane, the samples can be measured in a temporally successive manner so that each sample is in turn the sample that is currently being measured. 
     As the optical measurement instrument includes movable parts such as the mechanical support element  102  and the receptable element  111 , the optical measurement instrument is preferably equipped with transportation protection during transportation, e.g. during shipping. A known solution is to use a bolt  128  or some other suitable pin for locking the mechanical support element  102  and the receptable element  111  to the body structure  101 . The bolt  128  is capable of acting as a transportation protection element which is arranged to prevent the movable parts from moving during transportation and which has to be removed before the normal use of the optical measurement instrument. An inconvenience related to a technical solution of the kind described above is the work needed for installing the bolt  128  or another suitable pin to the optical measurement instrument before the transportation and also the work needed for removing the bolt or the other suitable pin after the transportation. For example, to be able to install the bolt  128  to the optical measurement instrument it is required that a hole  129 ,  FIG. 1   b , of the part  107  is sufficiently well aligned with the respective holes in the body structure  101  and in the mechanical support element  102 . 
     SUMMARY 
     In accordance with a first aspect of the invention, there is provided a new arrangement for equipping an optical measurement instrument with transportation protection, the said optical measurement instrument comprising:
         a body structure,   a first mechanical support element for supporting an optical interface capable of directing an excitation beam to a sample to be measured and/or to collect emission beam from the sample,   a receptable element for receiving a sample plate and being located in an area between the first mechanical support element and the body structure, and   second mechanical support elements arranged to moveably support the receptable element with respect to the body structure.       

     The arrangement according to the invention comprises a detachable transportation protection element that is arranged to be pressed between the first mechanical support element and the body structure so as to mechanically restrict movement of the receptable element with respect to the body structure. 
     As the transportation protection element is arranged to be pressed between the first mechanical support element and the body structure, there is no need to install e.g. a bolt or some other pin into holes of different parts of the optical measurement instrument and thus the need for positioning the said parts in such a manner that the said holes are aligned with respect to each other is avoided. 
     In conjunction with such an optical measurement instrument that comprises driving elements that can be used for adjusting the distance between the first mechanical support element and the body structure, the transportation protection element can be arranged to be pressed between the first mechanical support element and the body structure for example with the aid of the above-mentioned driving elements. The driving elements may comprise for example one or more threaded rods having the thread pitch angle so small that each threaded rod is self-locking by friction to a respective counterpart in the longitudinal direction of the one or more threaded rods. Hence, the first mechanical support element and the receptable element are bound to the body structure with the aid of the above-mentioned driving elements and the transportation protection element. It is also possible that the transportation protection element is arranged to expand as a response to a control action directed to the transportation protection element in order to arrange the transportation protection element to be pressed between the first mechanical support element and the body structure. The transportation protection element can be, for example, a balloon-like bag that is expanded with e.g. pressurised air. 
     In accordance with a second aspect of the invention, there is provided a new optical measurement instrument. The optical measurement instrument according to the invention is equipped with transportation protection and it comprises:
         a body structure,   a first mechanical support element for supporting an optical interface capable of directing an excitation beam to a sample to be measured and/or to collect emission beam from the sample,   a receptable element for receiving a sample plate and being located in an area between the first mechanical support element and the body structure,   second mechanical support elements arranged to moveably support the receptable element with respect to the body structure, and   a transportation protection element that is detachable and arranged to mechanically restrict movement of the receptable element with respect to the body structure,
 
wherein the transportation protection element is arranged to be pressed between the first mechanical support element and the body structure.
       

     In accordance with a third aspect of the invention, there is provided a new method for equipping an optical measurement instrument with transportation protection, the optical measurement instrument comprising:
         a body structure,   a first mechanical support element for supporting an optical interface capable of directing an excitation beam to a sample to be measured and/or to collect emission beam from the sample,   a receptable element for receiving a sample plate and being located in an area between the first mechanical support element and the body structure, and   second mechanical support elements arranged to moveably support the receptable element with respect to the body structure.       

     The method according to the invention comprises arranging a detachable transportation protection element to be pressed between the first mechanical support element and the body structure so as to arrange the transportation protection element to mechanically restrict movement of the receptable element with respect to the body structure. 
     A number of exemplifying embodiments of the invention are described in accompanied dependent claims. 
     Various exemplifying embodiments of the invention both as to constructions and to methods of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific exemplifying embodiments when read in connection with the accompanying drawings. 
     The verbs “to comprise” and “to include” are used in this document as open expressions that do not exclude the existence of also unrecited features. The features recited in depending claims are mutually freely combinable unless otherwise explicitly stated. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The exemplifying embodiments of the invention and their advantages are explained in greater detail below in the sense of examples and with reference to the accompanying drawings, in which: 
         FIG. 1   a  shows a schematic illustration of an optical measurement instrument according to the prior art, 
         FIG. 1   b  shows a schematic illustration of a view seen downwards from line A-A of  FIG. 1   a,    
         FIG. 2   a  shows a schematic illustration of an optical measurement instrument that is equipped according to an embodiment of the invention with a transportation protection element suitable for providing transportation protection, 
         FIG. 2   b  shows a schematic illustration of the optical measurement instrument of  FIG. 2   a  in a situation in which the transportation protection element is being used for providing the transportation protection, 
         FIG. 2   c  shows a schematic illustration of a view seen downwards from line A-A of  FIG. 2   b,    
         FIG. 3   a  shows a schematic illustration of an optical measurement instrument that is equipped according to an embodiment of the invention with a transportation protection element suitable for providing transportation protection, 
         FIG. 3   b  shows a schematic illustration of the optical measurement instrument of  FIG. 3   a  in a situation in which the transportation protection element is being used for providing the transportation protection, 
         FIG. 3   c  shows a schematic illustration of a view seen downwards from line A-A of  FIG. 3   b,    
         FIG. 4   a  shows a schematic illustration of an optical measurement instrument that is equipped according to an embodiment of the invention with a transportation protection element suitable for providing transportation protection, 
         FIG. 4   b  shows a schematic illustration of the optical measurement instrument of  FIG. 4   a  in a situation in which the transportation protection element is being used for providing the transportation protection, 
         FIG. 5   a  shows a schematic illustration of an optical measurement instrument that is equipped according to an embodiment of the invention with a transportation protection element suitable for providing transportation protection, 
         FIG. 5   b  shows a schematic illustration of the optical measurement instrument of  FIG. 5   a  in a situation in which the transportation protection element is being used for providing the transportation protection, 
         FIG. 6   a  shows a schematic illustration of an optical measurement instrument that is equipped according to an embodiment of the invention with a transportation protection element suitable for providing transportation protection, 
         FIG. 6   b  shows a schematic illustration of the optical measurement instrument of  FIG. 6   a  in a situation in which the transportation protection element is being used for providing the transportation protection, 
         FIG. 7   a  shows a schematic illustration of an optical measurement instrument that is equipped according to an embodiment of the invention with a transportation protection element suitable for providing transportation protection, 
         FIG. 7   b  shows a schematic illustration of the optical measurement instrument of  FIG. 7   a  in a situation in which the transportation protection element is being used for providing the transportation protection, 
         FIG. 7   c  shows a schematic illustration of a view seen downwards from line A-A of  FIG. 7   b,    
         FIG. 8  shows a flow chart of a method according to an embodiment of the invention for equipping an optical measurement instrument with transportation protection, and 
         FIG. 9  shows a flow chart of a method according to an embodiment of the invention for equipping an optical measurement instrument with transportation protection. 
         FIGS. 1   a  and  1   b  have been explained earlier in this document in conjunction with the background of the invention. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
       FIG. 2   a  shows a schematic illustration of an optical measurement instrument that is equipped with a detachable transportation protection element suitable for providing transportation protection.  FIG. 2   b  shows a schematic illustration of the optical measurement instrument in a situation in which the transportation protection element is being used for providing the transportation protection.  FIG. 2   c  shows a schematic illustration of a view seen downwards from line A-A of  FIG. 2   b.    
     The optical measurement instrument may include, among others, the following functional elements: an excitation light source, a detector, one or more optical filters, light guides, and an optical interface capable of directing an excitation beam to a sample to be measured and/or to collect emission beam from the sample. One or more of the above-mentioned functional elements may be changeable optical modules that are not necessarily present in the optical measurement instrument during transportation, e.g. shipping. Hence, the above-mentioned functional elements are not shown in  FIGS. 2   a - 2   c . Dashed line  223  represents a place for one or more optical components constituting the optical interface. 
     The optical measurement instrument includes a first mechanical support element  202  that is suitable for supporting the optical interface. As mentioned above, the said optical interface may be a changeable optical module that is not necessarily installed to the first mechanical support element  202 , or alternatively the optical interface may include optical components that are integral parts of the optical measurement instrument. The first mechanical support element  202  is connected to a body structure  201  of the optical measurement instrument with the aid of driving elements that allow the first mechanical support element  202  to be moved relative to the body structure  201  in the positive and negative z-directions of a co-ordinate system  290 . The co-ordinate system  290  is assumed to be fixed relative to the body structure  201 . In the optical measurement instrument shown in  FIGS. 2   a - 2   c , the driving elements include threaded rods  203  and  204  and respective counterparts  205  and  206  so as to allow the first mechanical support element  202  to be moved in the positive and negative z-directions of the co-ordinate system  290 . The counterparts  205  and  206  may include, for example, servomotors arranged to move the first mechanical support element  202  in the positive and negative z-directions of the co-ordinate system  290 . It should be noted that the threaded rods are not the only possible choice for providing the driving elements. The driving elements can as well be based on e.g. a toothed bar and a worm gear. 
     The optical measurement instrument includes a receptable element  211  that is suitable for receiving a sample plate. The optical measurement instrument includes second mechanical support elements arranged to moveably support the receptable element  211  with respect to the body structure  201 . The second mechanical support elements include a support rail  208  and guide elements  209  and  210  shown in  FIG. 2   b . The support rail  208  is supported relative to the body structure  201  with the aid of the guide elements  209  and  210  in such a manner that the support rail is movable in the directions of a two-headed arrow  226  shown in  FIG. 2   b . The receptable element  211  is connected with the aid of a part  207  to the support rail  208  in such a manner that the receptable element is capable of sliding along the support rail in the longitudinal direction of the support rail, i.e. the receptable element is movable in the directions of a two-headed arrow  227  shown in  FIG. 2   b . Hence, the receptable element  211  is movable in the xy-plane defined by the co-ordinate system  190 . Due to the fact that the receptable element  211  is movable in the xy-plane, samples can be measured during the normal use of the optical measurement instrument in a temporally successive manner so that each sample is in turn the sample that is currently being measured. 
     The above-mentioned sample plate is not shown in  FIGS. 2   a - 2   c , because, in the situations shown in  FIGS. 2   a - 2   c , the optical measurement instrument includes the transportation protection element that is located with respect to the receptable element  211  in a substantially similar manner as the sample plate is intended to locate with respect to the receptable element. The transportation protection element includes a first part  213  that is in mechanical contact with the receptable element  211  in a substantially similar manner as the sample plate is intended to be in mechanical contact with the receptable element. The transportation protection element further includes a second part  212  that is connected to the first part in a flexible manner with the aid of helical springs  214  and  215 . The helical springs allow the second part  212  to be pressed against the body structure  201  with the aid of the first mechanical support element  202  in the direction of an arrow  230 .  FIG. 2   b  illustrates a situation in which the first mechanical support element  202  presses the second part  212  of the transportation protection element against the body structure  201 . The driving elements that include the threaded rods  203  and  204  and the respective counterparts  205  and  206  are advantageously used for making the first mechanical support element  202  to press the second part  212  of the transportation protection element against the body structure  201 . The threaded rods  203  and  204  have advantageously the thread pitch angle so small that each threaded rod is self-locking by friction to a respective counterpart  205  or  206  in the longitudinal direction of the threaded rods, i.e. in the z-direction of the co-ordinate system  290 . The thread pitch angle can be e.g. 3-10 degrees. Hence, the first mechanical support element  202  and the receptable element  211  are bound to the body structure  201  with the aid of the above-mentioned driving elements and the transportation protection element. 
     In the following parts of this description of the exemplifying embodiments, a notation such as “the transportation protection element  212 - 215 ” means “the transportation protection element including the first part  213 , the second part  212 , and the helical springs  214  and  215 ”. Correspondingly, a notation such as “the driving elements  203 - 206 ” means “the driving elements including the threaded rods  203  and  204  and the respective counterparts  205  and  206 ”. The same is valid also for other figures. 
     As shown in  FIG. 2   a , the transportation protection element  212 - 215  is neither in mechanical contact with the first mechanical support element  202  nor in mechanical contact with the body structure  201 . Therefore, the transportation protection element can be placed to the receptable element  211  in a similar manner as a sample plate can be placed to the receptable element. After placing the transportation protection element to the receptable element, the receptable element and the transportation protection element can be driven to a desired position with the aid of the second mechanical support elements  207 - 210  that are arranged to moveably support the receptable element with respect to the body structure. After this, the driving elements that include the threaded rods  203  and  204  and the respective counterparts  205  and  206  can be used for making the first mechanical support element  202  to press the second part  212  of the transportation protection element against the body structure  201 . Hence, the optical measurement instrument can be equipped with transportation protection by replacing a sample plate with the transportation protection element  212 - 215  and by using the same parts of the optical measurement instrument, i.e. the first mechanical support element  201 , the second mechanical support elements  207 - 210 , and the driving elements  203 - 206 , that are also used during the normal operation of the optical measurement instrument, i.e. when the optical measurement instrument is used for measuring samples. 
     In an optical measurement instrument according to an embodiment of the invention a surface of the transportation protection element  212 - 215  that is in mechanical contact with the body structure  201  is at least partially covered with anti-slip material and/or a surface of the transportation protection element that is in mechanical contact with the first mechanical support element  202  is at least partially covered with anti-slip material. The anti-slip material can be for example rubber. 
       FIG. 3   a  shows a schematic illustration of an optical measurement instrument that is equipped with a detachable transportation protection element suitable for providing transportation protection.  FIG. 3   b  shows a schematic illustration of the optical measurement instrument in a situation in which the transportation protection element is being used for providing the transportation protection.  FIG. 3   c  shows a schematic illustration of a view seen downwards from line A-A of  FIG. 3   b . Except for the transportation protection element, the optical measurement instrument can be otherwise similar to the optical measurement instrument presented in  FIGS. 2   a - 2   c . Hence, the reference numbers  301 ,  302 ,  303 ,  304 ,  305 ,  306 ,  307 ,  308 ,  309 ,  310 ,  311 ,  323 ,  326 ,  327 , and  330  shown in  FIGS. 3   a - 3   c  correspond to reference numbers  201 - 211 ,  223 ,  226 ,  227 , and  230  shown in  FIGS. 2   a - 2   c , respectively. 
     The transportation protection element includes a first part  313  that is in mechanical contact with the receptable element  311  in a substantially similar manner as a sample plate is intended to be in mechanical contact with the receptable element. 
     The transportation protection element further includes a second part  312  connected to the first part  312  in a flexible manner so as to allow the second part to be pressed against the body structure  301  with the aid of the first mechanical support element  302  in the direction of the arrow  330 , as shown in  FIG. 3   b . The transportation protection element is made of elastic material and the first part  313  of the transportation protection element is connected to the second part  312  of the transportation protection element with strips of said elastic material as shown in  FIG. 3   c . The reference number  314  shown in  FIG. 3   c  refers to one of the said strips. The transportation protection element shown in  FIGS. 3   a - 3   c  can be cast as a single piece. The elastic material can be for example soft plastics or rubber. 
       FIG. 4   a  shows a schematic illustration of an optical measurement instrument that is equipped with a detachable transportation protection element suitable for providing transportation protection.  FIG. 4   b  shows a schematic illustration of the optical measurement instrument in a situation in which the transportation protection element is being used for providing the transportation protection. Except for the transportation protection element, the optical measurement instrument can be otherwise similar to the optical measurement instrument presented in  FIGS. 2   a - 2   c . Hence, the reference numbers  401 ,  402 ,  403 ,  404 ,  405 ,  406 ,  407 ,  408 ,  411 ,  423 , and  430  shown in  FIGS. 4   a  and  4   b  correspond to reference numbers  201 - 208 ,  211 ,  223 , and  230  shown in  FIGS. 2   a  and  2   b , respectively. 
     The transportation protection element  412  is a piece of material such as plastics or rubber and it is dimensioned to fit with the receptable element  411  as illustrated in  FIGS. 4   a  and  4   b . Due to the gravity, the transportation protection element  412  is in mechanical contact with the body structure  401  also in the situation shown in  FIG. 4   a . Hence, friction between the transportation protection element  412  and the body structure  401  is a disturbing issue when the transportation protection element  412  is moved to its desired position with the aid of the second mechanical support elements  407 ,  408  that are arranged to moveably support the receptable element  411 . The friction can be minimised by minimising the weight of the transportation protection element e.g. by making the transportation protection element hollow as shown in  FIGS. 4   a  and  4   b . In the situation shown in  FIG. 4   b , the driving elements  403 - 406  are arranged to make the mechanical support element  402  to press the transportation protection element  412  against the body structure  401  in the direction of the arrow  430 . 
       FIG. 5   a  shows a schematic illustration of an optical measurement instrument that is equipped with a detachable transportation protection element suitable for providing transportation protection.  FIG. 5   b  shows a schematic illustration of the optical measurement instrument in a situation in which the transportation protection element is being used for providing the transportation protection. Except for the transportation protection element and for a body structure  501 , the optical measurement instrument can be otherwise similar to the optical measurement instrument presented in  FIGS. 2   a - 2   c . Hence, the reference numbers  502 ,  503 ,  504 ,  505 ,  506 ,  507 ,  508 ,  511 ,  523 , and  530  shown in  FIGS. 5   a  and  5   b  correspond to reference numbers  202 - 208 ,  211 ,  223 , and  230  shown in  FIGS. 2   a  and  2   b , respectively. 
     The transportation protection element includes a first part  513  that is in mechanical contact with the receptable element  511  in a substantially similar manner as the sample plate is intended to be in mechanical contact with the receptable element. The transportation protection element further includes a second part  512  that is connected to the first part in a flexible manner with the aid of springs  514  and  515 . The springs allow the second part  512  to be pressed with the aid of the first mechanical support element  502  against the body structure  501  in the direction of the arrow  530 .  FIG. 5   b  illustrates a situation in which the first mechanical support element  502  presses the second part  512  of the transportation protection element against the body structure  501 . A surface of the second part  512  that is, in the situation shown in  FIG. 5   b , in mechanical contact with the body structure  501  is equipped with at least one projection  531  that is able to fit with a respective cavity  532  in the body structure. Due to the projection and the cavity, the locking effect achieved is not only based on the friction between the transportation protection element and the body structure. Thus, a smaller pressing force by which the first mechanical support element  502  presses the second part  512  of the transportation protection element may be sufficient than in a case without the said projection and cavity. 
       FIG. 6   a  shows a schematic illustration of an optical measurement instrument that is equipped with a detachable transportation protection element suitable for providing transportation protection.  FIG. 6   b  shows a schematic illustration of the optical measurement instrument in a situation in which the transportation protection element is being used for providing the transportation protection. The reference numbers  601 ,  602 ,  607 ,  608 ,  611 , and  623  shown in  FIGS. 6   a  and  6   b  correspond to reference numbers  201 ,  202 ,  207 ,  208 ,  211 , and  223  shown in  FIGS. 2   a  and  2   b , respectively. 
     The transportation protection element  612  is arranged to expand as a response to a control action directed to the transportation protection element in order to arrange the transportation protection element to be pressed between the first mechanical support element  602  and the body structure  601 .  FIGS. 6   a  and  6   b  shows an example in which the said transportation protection element is a balloon-like bag made of flexible material e.g. rubber or plastic. The transportation protection element shown in  FIGS. 6   a  and  6   b  can be expanded, for example, with pressurized air, i.e. the control action directed to the transportation protection element can be supplying pressurized air. Expandable transportation protection elements different from the one shown in  FIGS. 6   a  and  6   b  are also possible. For example, an expandable transportation protection element may include a spring that is arranged to push parts of the transportation protection element away from each other in order to expand the transportation protection element, and a screw or other control means for forcing the said parts closer to each other against the force generated by the spring. In this case the said control action may be e.g. turning a screw so that the spring is released to expand the transportation protection element. The expandable transportation protection elements of the kind described above are suitable also for cases in which the first mechanical support element  602  is not moveable relative to the body structure  601 . 
       FIG. 7   a  shows a schematic illustration of an optical measurement instrument that is equipped with a detachable transportation protection element suitable for providing transportation protection.  FIG. 7   b  shows a schematic illustration of the optical measurement instrument in a situation in which the transportation protection element is being used for providing the transportation protection.  FIG. 7   c  shows a schematic illustration of a view seen downwards from line A-A of  FIG. 7   b . Except for the transportation protection element, the optical measurement instrument can be otherwise similar to the optical measurement instrument presented in  FIGS. 2   a - 2   c . Hence, the reference numbers  701 ,  702 ,  703 ,  704 ,  705 ,  706 ,  707 ,  708 ,  709 ,  710 ,  711 ,  723 ,  726 ,  727 , and  730  shown in  FIGS. 7   a - 7   c  correspond to reference numbers  201 - 211 ,  223 ,  226 ,  227 , and  230  shown in  FIGS. 2   a - 2   c , respectively. The transportation protection element  712  is a piece of material such as plastics or rubber and it is positioned with respect to the receptable element  711  as illustrated in  FIGS. 7   a - 7   c . A situation in which the first mechanical support element  702  presses the transportation protection element  712  against the body structure  701  in the direction of the arrow  730  as shown in  FIG. 7   b.    
     Arrangements according to some exemplifying embodiments of the invention are described below referring to  FIGS. 2   a - 2   c ,  3   a - 3   c ,  4   a ,  4   b ,  5   a ,  5   b ,  6   a ,  6   b , and  7   a - 7   c , i.e. the numbers mentioned below are the reference numbers shown in the said figures. 
     An arrangement according to an embodiment of the invention includes a detachable transportation protection element  212 - 215 ,  312 - 314 ,  412 ,  512 - 515 ,  612 ,  712  for equipping an optical measurement instrument with transportation protection, the said optical measurement instrument including:
         a body structure  201 ,  301 ,  401 ,  501 ,  601 ,  701 ,   a first mechanical support element  202 ,  302 ,  402 ,  502 ,  602 ,  702  for supporting an optical interface capable of directing an excitation beam to a sample to be measured and/or to collect emission beam from the sample,   a receptable element  211 ,  311 ,  411 ,  511 ,  611 ,  711  for receiving a sample plate and being located in an area between the first mechanical support element and the body structure, and   second mechanical support elements  207 - 210 ,  307 - 310 ,  407 ,  408 ,  507 ,  508 ,  607 ,  608 ,  707 - 710  arranged to moveably support the receptable element with respect to the body structure.       

     In the above-mentioned arrangement, the detachable transportation protection element is arranged to be pressed between the first mechanical support element and the body structure so as to mechanically restrict movement of the receptable element with respect to the body structure. 
     In an arrangement according to an embodiment of the invention, the transportation protection element  212 - 215 ,  312 - 314 ,  412 ,  512 - 515 ,  612  is located with respect to the receptable element in a substantially similar manner as a sample plate is intended to locate with respect to the receptable element. 
     In an arrangement according to an embodiment of the invention, the transportation protection element includes:
         a first part  213 ,  313  in mechanical contact with the receptable element in a substantially similar manner as a sample plate is intended to be in mechanical contact with the receptable element, and   a second part  212 ,  312  connected to the first part in a flexible manner so as to allow the second part to be pressed against the body structure  201 ,  301  with the aid of the first mechanical support element  202 ,  302 .       

     In an arrangement according to an embodiment of the invention, the transportation protection element  312 - 314  is made of elastic material and the first part  313  of the transportation protection element is connected to the second part  312  of the transportation protection element with strips  314  of said elastic material. 
     In an arrangement according to an embodiment of the invention, a surface of the transportation protection element that is in mechanical contact with the body structure is at least partially covered with anti-slip material. 
     In an arrangement according to an embodiment of the invention, the transportation protection element  212 - 215 ,  312 - 314 ,  412 ,  512 - 515 ,  712  is arranged to be pressed between the first mechanical support element  202 ,  302 ,  402 ,  502 ,  702  and the body structure  201 ,  301 ,  401 ,  501 ,  701  with the aid of driving elements  203 - 206 ,  303 - 306 ,  403 - 406 ,  503 - 506 ,  703 - 706  of the optical measurement instrument, the driving elements being arranged to move the first mechanical support element relative to the body structure. 
     In an arrangement according to an embodiment of the invention, the first mechanical support element  202  is locked to a position, in which it presses the transportation protection element, with the aid of driving elements that include at least one threaded rod  203 ,  204  having the thread pitch angle so small that the threaded rod is self-locking by friction to a respective counterpart  205 ,  206  in the longitudinal direction of the threaded rod. 
     In an arrangement according to an embodiment of the invention, the transportation protection element  612  is arranged to expand as a response to a control action directed to the transportation protection element in order to arrange the transportation protection element to be pressed between the first mechanical support element  602  and the body structure  601 . 
       FIG. 8  shows a flow chart of a method according to an embodiment of the invention for equipping an optical measurement instrument with transportation protection, wherein the optical measurement instrument includes:
         a body structure,   a first mechanical support element for supporting an optical interface capable of directing an excitation beam to a sample to be measured and/or to collect emission beam from the sample,   a receptable element for receiving a sample plate and being located in an area between the first mechanical support element and the body structure, and   second mechanical support elements arranged to moveably support the receptable element with respect to the body structure,       

     The above-mentioned method includes arranging, in phase  801 , a detachable transportation protection element to be pressed between the first mechanical support element and the body structure so as to arrange the transportation protection element to mechanically restrict movement of the receptable element with respect to the body structure. 
     The method may include possible other method phases such as, for example, manufacturing or assembling the transportation protection element and/or packaging the optical measurement instrument. 
     In a method according to an embodiment of the invention, the transportation protection element is placed with respect to the receptable element in a substantially similar manner as a sample plate is intended to locate with respect to the receptable element. 
     In a method according to an embodiment of the invention, a surface of the transportation protection element that is in mechanical contact with the body structure is at least partially covered with anti-slip material. 
     In a method according to an embodiment of the invention, the method includes pressing, with the aid of the first mechanical support element, the transportation protection element against the body structure. 
     In a method according to an embodiment of the invention, the first mechanical support element is pressed against the transportation protection element using least one threaded rod having a thread pitch angle so small that the threaded rod is self-locking by friction to a respective counterpart in the longitudinal direction of the threaded rod. 
     In a method according to an embodiment of the invention, the method includes expanding the transportation protection element in order to arrange the transportation protection element to be pressed between the first mechanical support element and the body structure. 
       FIG. 9  shows a flow chart of a method according to an embodiment of the invention for equipping an optical measurement instrument of the kind described above with transportation protection. In the method according to this embodiment of the invention, the transportation protection element includes a first part and a second part connected to the first part in a flexible manner, and the method includes:
         placing, in phase  901 , the first part into mechanical contact with the receptable element in a substantially similar manner as a sample plate is intended to be in mechanical contact with the receptable element, and   pressing, in phase  902 , the second part against the body structure with the aid of the first mechanical support element.       

     In a method according to an embodiment of the invention, the transportation protection element is made of elastic material and the first part of the transportation protection element is connected to the second part of the transportation protection element with strips of said elastic material. 
     The specific examples provided in the description given above should not be construed as limiting. Therefore, the invention is not limited merely to the embodiments described above.