Abstract: Provided is an objective optical system including: a first spherical lens and a second spherical lens that are arrayed in this order from an object; and at least one of a first optical medium and a second optical medium, wherein the first optical medium is a solid or liquid disposed at an object side of the first spherical lens and is in close contact with a surface on the object side of the first spherical lens, over an entire optical path; and the second optical medium is a solid or liquid disposed at an opposite side of the second spherical lens from the object and is in close contact with a surface on the opposite side of the second spherical lens from the object, over the entire optical path.

Abstract: An optical-scanning-type observation probe is provided with: an imaging optical system that illumination light scanned by an optical scanner enters and that focuses the illumination light in the form of a spot, multiple times; a projection optical system that emits illumination light coming from a focus position focused by the imaging optical system, toward a subject in the form of a spot; and a light-receiver that is provided independently of the imaging optical system and the projection optical system and that receives reflected light of the illumination light, the reflected light coming from the subject, via a light path different from that of the imaging optical system and the projection optical system.

Abstract: Provided is an objective optical system including: a first spherical lens and a second spherical lens that are arrayed in this order from an object; and at least one of a first optical medium and a second optical medium, wherein the first optical medium is a solid or liquid disposed at an object side of the first spherical lens and is in close contact with a surface on the object side of the first spherical lens, over an entire optical path; and the second optical medium is a solid or liquid disposed at an opposite side of the second spherical lens from the object and is in close contact with a surface on the opposite side of the second spherical lens from the object, over the entire optical path.

Abstract: The disclosed technology is directed to a light detecting apparatus used in an image acquiring apparatus. The image acquiring apparatus comprises a light receiving element that outputs a current according to a light amount of incident light. A current-voltage conversion circuit converts the current output from the light receiving element to a voltage signal. The current-voltage conversion circuit includes an operational amplifier and feedback resistance, feedback capacitance, and at least one diode that are connected in parallel between an inverting terminal and an output terminal of the operational amplifier. The diode is connected to have a forward direction from the inverting terminal toward the output terminal, and following conditional expressions are satisfied, G=Rf B=1/(2?Rf(Cf+Cd/n)) and Vpr>n×Vf>G×Imax.

Abstract: The disclosed optical scanning endoscope apparatus includes a scanner that scans an object with illumination light from a light source, a light amount detector that detects a light amount of the illumination light from the light source, and a controller that controls output of the light source based on the light amount detected by the light amount detector. The controller controls the output of the light source based on an integral value of the light amount detected by the light amount detector during an immediately prior predetermined period.

Abstract: Provided is a scanning endoscope system including: an illumination-light emitting portion that is inserted into a body of a patient and that emits illumination light emitted from a light-source portion toward an imaging subject in the body in a spot-like manner; a light scanner that scans the illumination light on the imaging subject; and a light detector that is disposed at a body surface of the patient, and that detects reflected light coming from the scanning position in the imaging subject, at which the illumination light is scanned by the light scanner.

Abstract: An optical-scanning-type observation probe is provided with: an imaging optical system that illumination light scanned by an optical scanner enters and that focuses the illumination light in the form of a spot, multiple times; a projection optical system that emits illumination light coming from a focus position focused by the imaging optical system, toward a subject in the form of a spot; and a light-receiver that is provided independently of the imaging optical system and the projection optical system and that receives reflected light of the illumination light, the reflected light coming from the subject, via a light path different from that of the imaging optical system and the projection optical system.

Abstract: The disclosed technology is directed to a light detecting apparatus used in an image acquiring apparatus. The image acquiring apparatus comprises a light receiving element that outputs a current according to a light amount of incident light. A current-voltage conversion circuit converts the current output from the light receiving element to a voltage signal. The current-voltage conversion circuit includes an operational amplifier and feedback resistance, feedback capacitance, and at least one diode that are connected in parallel between an inverting terminal and an output terminal of the operational amplifier. The diode is connected to have a forward direction from the inverting terminal toward the output terminal, and following conditional expressions are satisfied, G=Rf B=1/(2?Rf(Cf+Cd/n)) and Vpr>n×Vf>G×Imax.

Abstract: Provided is a scanning endoscope system including: an illumination-light emitting portion that is inserted into a body of a patient and that emits illumination light emitted from a light-source portion toward an imaging subject in the body in a spot-like manner; a light scanner that scans the illumination light on the imaging subject; and a light detector that is disposed at a body surface of the patient, and that detects reflected light coming from the scanning position in the imaging subject, at which the illumination light is scanned by the light scanner.

Abstract: Provided is a scanning endoscope system including an illumination-light emitting unit that outputs illumination light emitted from a light source in a spot-like manner toward a subject, a light scanner that scans the illumination light output from the illumination-light emitting unit over the subject, and a light detector that is provided in a movable manner relative to the illumination-light emitting unit and that detects reflection light from a scan position on the subject over which the illumination light is scanned by the light scanner.

Abstract: Provided is a scanning endoscope apparatus capable of generating an image having an optimum SNR. The scanning endoscope apparatus includes: a light source; an optical fiber that guides light emitted from the light source; an actuator that deflects light emitted from the optical fiber and repeatedly scans the deflected light on the irradiation object; a light detector with a controllable multiplication factor, the light detector photoelectrically converting signal light obtained from the irradiation object irradiated with the light; and a controller, the controller controlling the multiplication factor so as to optimize a SNR based on electric signals obtained for a certain period, the signals having been photoelectrically converted by the optical detection unit.

Abstract: This optical scanning endoscope apparatus can correct the white balance even when bending occurs in the illumination fiber. An optical scanning endoscope apparatus includes an illumination fiber that guides illumination light composed of RGB wavelengths (colors), an actuator that drives the tip of the illumination fiber and repeatedly scans the illumination light over an object, a photodetector that detects light obtained from the object by scanning of the illumination light, a signal processor that generates an image based on output of the photodetector, and a light amount detector for white balance that detects the light amount of light of RGB wavelengths from a portion of the illumination light guided by the illumination fiber. Based on the light amount of light of each of the RGB wavelengths detected by the light amount detector for white balance, the controller adjusts the white balance of the generated image.

Abstract: This optical scanning endoscope apparatus includes an actuator that scans light from a light source over an object with a predetermined scan cycle, a light amount detector that detects the light amount from the light source, and a controller that controls output of the light source based on the light amount detected by the light amount detector. During each scan cycle by the actuator, the controller controls the light source so as to output light according to a predetermined output change pattern, sequentially calculates an integral value of the light amount detected by the light amount detector over a predetermined time period, and controls the maximum of the change in output of the light source due to the output change pattern so that the integral value does not exceed a predetermined standard value.

Abstract: The disclosed optical scanning endoscope apparatus includes a scanner that scans an object with illumination light from a light source, a light amount detector that detects a light amount of the illumination light from the light source, and a controller that controls output of the light source based on the light amount detected by the light amount detector. The controller controls the output of the light source based on an integral value of the light amount detected by the light amount detector during an immediately prior predetermined period.

Abstract: A nerve stimulation apparatus performs nerve stimulation of a required level while reducing the adverse effect on the heart and on the detection of a cardiac event. Provided is a nerve stimulation apparatus that includes a stimulation signal output unit that outputs a nerve stimulation signal; a cardiac event detector that detects a cardiac event; and a controller that controls the stimulation signal output unit so as to output a nerve stimulation signal having a smaller intensity in a non-refractory period than that in a cardiac refractory period that is obtained on the basis of the cardiac event detected by the cardiac event detector.

Abstract: Provided is a cardiac-event processor (1) including a storing unit (11) that stores a time history of cardiac events, including heartbeats, in association with the presence/absence of nerve stimulation; a heart rate calculator (12) that calculates a heart rate for when each heartbeat is detected, on the basis of the time history of the cardiac events stored in the storing unit (11); and a frequency data generator (13) that separately adds up frequencies of the heart rates calculated by the heart rate calculator (12) for the cases with and without the nerve stimulation.

Abstract: Provided is a nerve stimulation apparatus that is capable of performing effective nerve stimulation depending on a therapeutic purpose without adversely affecting a heart. Further provided is a nerve stimulation apparatus including: a stimulation-pulse output unit that outputs a stimulation pulse; a cardiac-event detector that detects a cardiac event; and a controller that controls the stimulation-signal output unit so as to output, during a cardiac refractory period, the nerve stimulation signal having an intensity that corresponds to the heart rate obtained on the basis of the cardiac event detected by the cardiac-event detector.

Abstract: Provided is a nerve stimulation apparatus that is capable of performing effective nerve stimulation depending on a therapeutic purpose without adversely affecting a heart. Further provided is a nerve stimulation apparatus including: a stimulation-pulse output unit that outputs a stimulation pulse; a cardiac-event detector that detects a cardiac event; and a controller that controls the stimulation-signal output unit so as to output, during a cardiac refractory period, the nerve stimulation signal having an intensity that corresponds to the heart rate obtained on the basis of the cardiac event detected by the cardiac-event detector.

Abstract: A nerve stimulation apparatus performs nerve stimulation of a required level while reducing the adverse effect on the heart and on the detection of a cardiac event. Provided is a nerve stimulation apparatus that includes a stimulation signal output unit that outputs a nerve stimulation signal; a cardiac event detector that detects a cardiac event; and a controller that controls the stimulation signal output unit so as to output a nerve stimulation signal having a smaller intensity in a non-refractory period than that in a cardiac refractory period that is obtained on the basis of the cardiac event detected by the cardiac event detector.

Abstract: Provided is a cardiac-event processor (1) including a storing unit (11) that stores a time history of cardiac events, including heartbeats, in association with the presence/absence of nerve stimulation; a heart rate calculator (12) that calculates a heart rate for when each heartbeat is detected, on the basis of the time history of the cardiac events stored in the storing unit (11); and a frequency data generator (13) that separately adds up frequencies of the heart rates calculated by the heart rate calculator (12) for the cases with and without the nerve stimulation.