Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power; a second lens unit having a negative refractive power; and a third lens unit having a positive refractive power. The first lens unit does not move and the second lens unit and the third lens unit move in mutually different loci during zooming. Conditional expressions are satisfied as follows: 0.05<|f2/m2|<0.59, and 0.20<|f3/m3|<1.95, where f2 is a focal length of the second lens unit, f3 is a focal length of the third lens unit, m2 is a moving amount of the second lens unit during zooming from a wide-angle end to a telephoto end, and m3 is a moving amount of the third lens unit during zooming from the wide-angle end to the telephoto end.

Abstract: A zoom lens includes, in order from an object side to an image side: a negative first lens unit; a negative second lens unit; and a positive third lens unit, in which the first lens unit is not moved for zooming, the second lens unit and the third lens unit are moved during zooming, and an interval between each pair of adjacent lens units is changed during zooming, in which the first lens unit includes at least two negative lenses, and a focal length of the first lens unit, a focal length of the zoom lens at a wide angle end, a focal length of the zoom lens at a telephoto end, an interval on an optical axis between the first lens unit and the second lens unit at the wide angle end, and a back focus at the wide angle end are appropriately set.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, a third lens unit having a positive refractive power, a rear lens group including one or more lens units, and an aperture stop. During zooming, with the first lens unit not moving, the second lens unit and at least one of the lens units of the rear lens group move. In this zoom lens, the configuration of the third lens unit and the location of the aperture stop are appropriately set.

Abstract: A biological signal acquirer is attached to a subject and acquires a biological signal of the subject. A transmitter carried by the subject transmits the biological signal. A first communication port and a first camera are installed in a first location and connectable to a network. A second communication port and a second camera are installed in a second location and connectable to the network. A biological information acquiring device is connectable to the network and provided with a switcher. The switcher acquires, when communication establishment between the transmitter and the first communication port is detected, the biological signal through the first communication port as well as a first image taken by the first camera, and acquires, when communication establishment between the transmitter and the second communication port is detected, the biological signal through the second communication port as well as a second image taken by the second camera.

Abstract: In a zoom lens including a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a third lens unit having a positive refractive power that are arranged in order from an object side to an image side, a movement locus of each of the lens units, an amount of movement of the third lens unit when zooming from a wide angle end to a telephoto end, and a focal length of the third lens unit are set as appropriate.

Abstract: A transmission device can be carried by the subject. A biological signal recording device can perform wireless communication with the transmission device. A transmitter transmits biological signal data corresponding to a biological signal of a subject. A storage stores the biological signal data. A receiver receives the biological signal data. A recorder records the biological signal data received by the receiver. A detector detects a missing portion in the biological signal data recorded by the recorder or a receipt of the biological signal data by the receiver. A notifier notifies the missing portion or transmits an acknowledgment of the receipt to the transmission device. A complementary transmitter retrieves biological signal data corresponding to the notified missing portion from the storage or identifies unreceived biological signal data and retrieves the identified biological signal data, and transmits the retrieved biological signal data.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, a third lens unit having a positive refractive power, a rear lens group including one or more lens units, and an aperture stop. During zooming, with the first lens unit not moving, the second lens unit and at least one of the lens units of the rear lens group move. In this zoom lens, the configuration of the third lens unit and the location of the aperture stop are appropriately set.

Abstract: In a zoom lens including a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a third lens unit having a positive refractive power that are arranged in order from an object side to an image side, a movement locus of each of the lens units, an amount of movement of the third lens unit when zooming from a wide angle end to a telephoto end, and a focal length of the third lens unit are set as appropriate.

Abstract: Provided is an eyepiece lens to be used for observing an image displayed on an image displaying surface, the eyepiece lens consisting of, in order from the image displaying surface side to an observation side: a first lens unit having a negative refractive power; and a second lens unit having a positive refractive power. The first lens unit consists of one negative lens, and the second lens unit consists of, in order from the image displaying surface side to the observation side, a positive lens and a negative lens that has a concave surface facing the observation side. During adjustment of a diopter, the first lens unit is configured to not move, and the second lens unit is configured to move.

Abstract: In an infrared image capture device, an infrared optical system (10) has an objective optical system (13) that includes a primary mirror (11) and an auxiliary mirror (12) disposed to face each other along an optical axis (AX), and forms an intermediate image of an object (not illustrated) by sequentially reflecting the infrared ray from the object using the primary mirror (11) and the auxiliary mirror (12), and a non-transmitting portion (12f) which does not transmit the infrared rays from the object exists in the center portion of the auxiliary mirror (12). The non-transmitting portion (12f) in the center portion of the auxiliary mirror (12) is formed in a concave surface which satisfies a following conditional expression (1): L/1.2<R<1.

Abstract: An alignment device is provided for aligning a primary mirror with a secondary mirror in an optical system having the primary mirror and the secondary mirror arranged so as to face each other along the optical axis. The alignment device has a dichroic film formed on a surface on the front side of the secondary mirror and configured to reflect light used in the optical system and to transmit alignment light, a back reflecting surface formed on the back side of the secondary mirror and configured to reflect the alignment light, and a detection system which detects a positional deviation between the primary mirror and the secondary mirror, based on the alignment light having traveled via the dichroic film, the back reflecting surface, and a reflecting surface of the primary mirror.

Abstract: An alignment device is provided for aligning a primary mirror with a secondary mirror in an optical system having the primary mirror and the secondary mirror arranged so as to face each other along the optical axis. The alignment device has a dichroic film formed on a surface on the front side of the secondary mirror and configured to reflect light used in the optical system and to transmit alignment light, a back reflecting surface formed on the back side of the secondary mirror and configured to reflect the alignment light, and a detection system which detects a positional deviation between the primary mirror and the secondary mirror, based on the alignment light having traveled via the dichroic film, the back reflecting surface, and a reflecting surface of the primary mirror.

Abstract: A measurement apparatus and a receiver apparatus are communicatively connected in a wireless manner. Biological signal data is obtained from a detector attached on a living body. A data packet is prepared from the biological signal data. A first CRC of the biological signal data is calculated and appended to the data packet. The data packet is periodically transmitted with the first CRC from the measurement apparatus to the receiver apparatus. A second CRC of the data packet received at the receiver apparatus is calculated. The received data packet is verified when the second CRC is coincident with the first CRC. Acknowledgement data is transmitted from the receiver apparatus to the measurement apparatus when the received data packet is verified. The data packet is retransmitted from the measurement apparatus to the receiver apparatus when the acknowledgement data is not received at the measurement apparatus within a prescribed time period from a previous transmission of the data packet.

Abstract: A measurement apparatus and a receiver apparatus are communicatively connected in a wireless manner. Biological signal data is obtained from a detector attached on a living body. A data packet is prepared from the biological signal data. A first CRC of the biological signal data is calculated and appended to the data packet. The data packet is periodically transmitted with the first CRC from the measurement apparatus to the receiver apparatus. A second CRC of the data packet received at the receiver apparatus is calculated. The received data packet is verified when the second CRC is coincident with the first CRC. Acknowledgement data is transmitted from the receiver apparatus to the measurement apparatus when the received data packet is verified. The data packet is retransmitted from the measurement apparatus to the receiver apparatus when the acknowledgement data is not received at the measurement apparatus within a prescribed time period from a previous transmission of the data packet.