a detailed description of one preferred embodiment of a laser treatment apparatus embodying the present invention will now be given referring to the accompanying drawings . fig1 is a schematic perspective view of the laser treatment apparatus in the embodiment . as shown in fig1 the laser treatment apparatus is provided with a laser unit 1 , a multi - jointed arm 2 , a hand - piece unit 3 having a laser emission port , a cable 4 , a connector 5 , air tubes 6a and 6b , a control panel 7 which is used by the operator to set laser irradiation conditions , etc ., and a foot switch 8 which is depressed by the operator to produce a trigger signal whereby to emit a laser beam . the connector 5 is provided with a microswitch 42 for detecting the connection or disconnection of the cable 4 . also , a key switch 9 for turning on / off the power to the laser unit 1 is provided on a front part of the laser unit 1 . the laser unit 1 further includes an air purge pump 43 , a smoke evacuator 44 , a controller 40 which will be described later , a laser source 31 for emitting a treatment laser beam , an aiming light source 32 , and others . the air purge pump 43 and the smoke evacuator 44 are installed in the laser unit 1 with rubber attachment members whereby to prevent the vibration caused by the activation of the air purge pump 43 and the smoke evacuator 44 from being transmitted to the whole apparatus . the installation of the air purge pump 43 and the smoke evacuator 44 in the laser unit 1 needs not an extra installation space for them , and also the cables connecting the air purge pump 43 and the smoke evacuator 44 to the controller 40 do not become obstacles to an operator . in this embodiment , the treatment laser source 31 is a co2 laser source that emits an infrared laser beam , and the aiming light source is a semiconductor laser that emits a visible red laser beam . the multi - jointed arm 2 is made up of several rigid pipes movably linked by joints , so that the operator can move freely the hand - piece unit 3 which is attached at the end of the arm 2 . mirrors are fitted in the joints of the multi - joint arm 2 so that the treatment laser beam and aiming light beam that are aligned coaxially with each other in the laser unit 1 are guided to pass through the multi - jointed arm 2 and reach the hand - piece unit 3 . the hand - piece unit 3 is among a variety of detachable units designed to meet individual purposed and usage . for the following explanation of this embodiment , the apparatus is equipped with a scanning hand - piece unit 3 provided with a scanner head which deflects the laser beam to scan the treatment portion of a patient . fig2 is an explanatory view of a hand - piece unit of the laser treatment apparatus . the hand - piece unit 3 consists of a scanner 10 and a hand - piece head 11 which are separable . the scanner 10 incorporates driven mirrors 12a and 12b which deflect the treatment laser beam and aiming light beam , which have come through the multi - joint arm 2 , to scan the treatment portion in the x / y directions , drive motors 17a and 17b which swing the mirrors 12a and 12b , and a focusing lens 13 . the drive motors 17a and 17b are controlled by a scanner controller 41 provided in the laser unit 1 . the controller 40 produces drive currents , which are fed through the connector 5 and cable 4 to the drive motors 17a and 17b in the scanner 10 , by which the driven mirrors 12a and 12b are swung . the hand - piece head 11 is made of transparent resin , having a generally cone shape to cover the laser scanning area at its bottom , so that the operator can view from outside the treating area and irradiation area covered by the hand - piece head 11 . the hand - piece head 11 has in its side wall the formation of an air jet port 14 through which air is introduced to prevent stains caused by the smoke generated from the treating area during laser irradiation from being stuck to the optical system including the condensing lens 13 arranged at the laser emission port , a smoke outlet 15 which clears the treating area of smoke produced by the laser irradiation . in operation , a jet of air produced by the air purge pump 43 in the laser unit 1 is conducted through the air tube 6a to the air jet port 14 located near the top of the hand - piece head 11 . an evacuation of smoke , on the other hand , is conducted by the smoke evacuator 44 in the laser unit 1 , which sucks the smoke through the air tube 6b . incidentally , the bottom of hand - piece head 11 has the size which can secure the scanning area of the laser beam for the treatment . the operation of the apparatus constructed as above will be described below , referring to fig3 and 4 . fig3 is a block diagram of an electric system to activate an air purge pump 43 and a smoke evacuator 44 . fig4 is a block diagram of a main structure including a control system of the laser treatment apparatus . when the key switch 9 is turned on to actuate the laser unit 1 , an ac input section 50 produces a current to power relays 51a and 51b . on receiving the current , the power relays 51a and 51b generate a magnetic field with magnetic power to turn on switches 52a and 52b for the air purge pump 43 and switches 52c and 52d for the smoke evacuator 44 respectively . the pump switches 52a and 52b and the evacuator switches 52c and 52d turned on allow the current to flow in the air purge pump 43 and the smoke evacuator 44 , thereby activating them . the air supplied from the air purge pump 43 is fed to the hand - piece unit 3 through the air tube 6a and jetted through the air jet port 14 of the hand - piece head 11 . on the other hand , the air in the head 11 is sucked by the smoke evacuator 44 through the smoke outlet 15 and the air tube 6b . as shown in fig3 a manual switch 53a for pump and a manual switch 53b for evacuator are provided . they are connected with contact points at an initial state where the key switch 9 is turned on . in the above embodiment , two switches are provided for each of the air purge pump 43 and the smoke evacuator 44 because even if one of the switches is broken down and thus continuously kept as turned on , another switch can be turned off by turning off the key switch 9 to surely stop the operation of the air purge pump 43 and the smoke evacuator 44 . however , those switches may be one each for the pump and the evacuator . turning on the key switch 9 causes the current to flow in each section of the apparatus , the apparatus implements a self - check and displays a message of &# 34 ; self - check state &# 34 ; in a display on the control panel 7 . upon completion of the check for each section , the control unit 40 automatically enters the standby state , causing the control panel 7 to display a message of &# 34 ; standby state &# 34 ; thereon . in the self - check ( or during the power - on period ), the controller 40 checks the connection of the cable 4 to the connector 5 by means of a microswitch 42 . if disconnection is detected , the controller 40 cuts off the power supply to the scanner controller 41 , thereby preventing the malfunctioning of the apparatus . the operator confirms the apparatus in a standby state by viewing the display on the control panel 7 , and brings the entire bottom plane of the hand - piece unit 3 in contact with the patient &# 39 ; s body so as to cover the treatment portion . in the case of the treatment by scanning treatment laser , the operator depresses in advance a key on the control panel 7 to select a scan mode of an irradiation mode . from the hand - piece unit 3 , the aiming light beam emitted from the aiming light source 32 is irradiated to the treating area . while observing the irradiation position by the aiming light , the operator selects irradiation conditions , for example , an irradiation pattern , the shape of an irradiation area , the size of same , with the keys on the control panel 7 , and make a fine adjustment of the irradiation position with an alignment key . at this time , since the hand - piece head 11 is made of transparent resin , the operator can easily observe the irradiation position and the irradiation area and the like even if the treatment portion is covered by the hand - piece head 11 with its bottom brought into contact with the patient &# 39 ; s body . the hand - piece head 11 being formed into a substantially cone , its bottom comes into contact almost uniformly with the patient &# 39 ; s body . accordingly , the distance from the laser emission port or end of the scanner 10 to the treating area can be kept stably , and the operator can easily hold the hand - piece unit 3 in that state . the head 11 is in contact with the patient &# 39 ; s body , skin , in a relatively large contact area , dispersing the force of pressing the skin , which prevents the peripheral portion of the treating area from easily deforming . this makes it possible to provide a constant stable irradiation distance . after the setting of the irradiation conditions and the determination of the area to be irradiated based on the observation of the aiming light beam , the operator pushes a ready / standby key on the control panel 7 so that the apparatus turns to a ready state . then , the operator depresses the foot switch 8 to generate a trigger signal . the controller 40 which has received the trigger signal operates on the laser source 31 to emit a treatment laser beam in accordance with the setting irradiation conditions . the treatment laser beam emitted from the laser source 31 is reflected by a mirror 33 and the a dichroic mirror 34 , aligned coaxially to the aiming light beam emitted from the aiming light source 32 , and introduced to the multi - jointed arm 2 . the coaxial treatment laser beam and aiming light beam are reflected by the mirrors disposed at the joints of the arm 2 and led to the hand - piece unit 3 . the scanner controller 41 operates on the driving motors 17a and 17b in accordance with the setup signals of the form and size of irradiation area . in this way , the treatment laser beam is deflected to scan the diseased portion . when the scanning hand - piece unit 3 is used , signals are constantly transmitted - received between the scanner controller 41 and the hand - piece unit 3 through the connector 5 . when no feed back signal is returned from the hand - piece unit 3 to the scanner controller 41 , an error message is displayed . when the cable 4 is merely disconnected with the connector 5 , the controller 40 cuts off the power supply to the scanner controller 41 based on the detection signal from the microswitch 42 and causes the control panel 7 to display the message informing that the laser scanning hand - piece unit 3 is not connected to the laser unit 1 . accordingly , the operator can confirm whether the apparatus is in the connection error between the scanner controller 41 and the hand - piece unit 3 or the only disconnection of the cable 4 to the connector 5 , and take an appropriate measure . a hand - piece unit different from the laser scanning hand - piece unit 3 needs no operation of the scanner controller 41 . the controller 40 therefore cuts off the power supply to the scanner controller 41 in accordance with the information on the connection state of the cable 4 to the connector 5 , so that the apparatus does not enter a scan mode even if the operator select in mistake the scan mode , thereby preventing the malfunctioning of the apparatus . during laser irradiation , though the smoke is generated from the irradiated portion , the air is jetted thereto through the air jet port 14 of the hand - piece head 11 and the smoke is sucked through the smoke outlet 15 , thereby eliminating the smoke generated at the irradiated portion outward the head 11 . since the air purge pump 43 and the smoke evacuator 44 have been activated at the time of input of the key switch 9 which is turned on to activate the apparatus , the operator has not to additionally operate any switch to eliminate the smoke and can perform a laser irradiation operation on the diseased portion while observing it . it is also possible to prevent stains caused by the smoke from being stuck to the optical system provided in the vicinity of the laser emission port of the hand - piece head 11 . if not needed , the air supply may be stopped with the manual switch 53a and the smoke evacuation ( the air suction ) may be stopped with the manual switch 53b , respectively . these manual switches 53a and 53b may be either a common switch for the air supply and the smoke evacuation or separate switches . when the key switch 9 is turned off to cut off the power supply to the laser unit 1 after completion of the laser treatment , the pump switches 52a and 52b and the evacuator switches 52c and 52d become off , thus stopping the air purge pump 43 and the smoke evacuator 44 . in the above embodiment , the air purge pump 43 and the smoke evacuator 44 are activated interlocking with the on / off state of the key switch 9 ; however , they may be operated interlocking with the input of other keys , for example , the ready / standby key . also , the air purge pump 43 and the smoke evacuator 44 may be activated in response to the input signal from the foot switch 8 depressed for performing laser irradiation . the operation in this case will be described with reference to an electric system shown in fig5 wherein the same structures as in fig3 and 4 are provided with the same numbers . turning on the key switch 9 makes the pump switches 52a and 52b and the evacuator switches 52c and 52d become on , while a switch 54a disposed between the manual switch 53a and the air purge pump 43 and another switch 54b disposed between the manual switch 53b and the smoke evacuator 44 are in an off state . at this state , the air purge pump 43 and the smoke evacuator 44 are at rest . when the foot switch 8 is depressed after completion of the preparation for laser irradiation , a trigger signal is input to the controller 40 , thereby causing the laser source 31 to emit a treatment laser beam . the controller 40 keeps the switches 54a and 54b turning on during actuation of the laser source 31 and continuously a predetermined time α . consequently , the air purge pump 43 and the smoke evacuator 44 are activated during the laser irradiation to jet and suck air from the hand - piece unit 3 in order to eliminate the smoke generated from the laser irradiated portion of the skin . the air purge pump 43 and the smoke evacuator 44 are operated continuously for the predetermined time α after completion of the laser irradiation , thereby fully eliminating the smoke generated from the laser irradiated portion for a while after completion of the laser irradiation . the air purge pump 43 may be interlocked with the on / off state of the key switch 9 and the smoke evacuator 44 may be interlocked with the input signal from the foot switch 8 . an input device may be provided in the control panel 7 or the laser unit 1 of the apparatus , whereby to optionally set an air supply amount per hour from the air purge pump 43 . with the input device , the controller 40 may operate the air purge pump 43 so as to regulate the air supply amount . this makes it possible to supply air of an appropriate amount even when an amount of the smoke generated changes depending on treatment conditions and cases . similarly , it may be constructed so as to optionally set an air suction ( elimination ) amount per hour by the smoke evacuator 44 . the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof . for instance , the apparatus may be designed such that the smoke evacuator 44 and the air tube 6b are omitted and the air jetting through the air jet port 14 from the air purge pump 43 makes the smoke be discharged outside through the smoke outlet 15 . in this case , the smoke outlet 15 is preferably formed into plural cut portions as shown in fig6 ( a ). if the hand - piece head 11 is designed so that its bottom come into contact with the periphery of an diseased portion in at least three points , an operator can hold the hand - piece unit 3 in a stable state . in the above case of omitting the smoke evacuator 44 , the smoke outlet 15 may be omitted if the head 11 is provided with long contact portions as shown in fig6 ( b ). as mentioned above , the present invention can provide and keep a stable irradiation distance from the laser emission end port to the diseased portion , preventing the malfunctioning of the apparatus due to a replacement of hand - pieces . according to the present invention , furthermore , an installation space of the whole apparatus can be reduced and the operability to activate the air pump can be improved , preventing the operator from forgetting the activation of the air pump . it is therefore possible to eliminate the smoke generated due to the laser irradiation and to prevent stains due to the smoke from sticking to the optical system disposed in the vicinity of the laser emission port . the foregoing description of the preferred embodiment of the invention has been presented for purposes of illustration and description . it is not intended to be exhaustive or to limit the invention to the precise form disclosed , and modifications and variations are possible in light of the above teachings or may be acquired from practice of the invention . the embodiment chosen and described in order to explain the principles of the invention and its practical application to enable one skilled in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated . it is intended that the scope of the invention be defined by the claims appended hereto , and their equivalents .
a laser treatment apparatus has a hand - piece unit with a laser scanner which deflects a laser beam emitted from a laser source to scan a treatment portion of a patient &# 39 ; s skin . in the laser treatment apparatus , the first control device controls the laser scanner to perform a laser scanning irradiation . the detection device detects whether the hand - piece unit is electrically connected with the first control device . when the detection device detects the electrical disconnection of the hand - piece unit to the first control device , the second control device forbids the first control device to conduct the laser scanning irradiation .