A measurement device includes a measurement unit that measures a physical property of a measurement target by causing the measurement target to vibrate through an application of an ultrasonic wave, the measurement unit including a first mode that measures the physical property using a first burst wave sensitive in a first predetermined range of physical property values and a second mode that measures the physical property using a second burst wave sensitive in a second range of physical property values different from the first range, and a control unit that controls the measurement unit to execute at least one of the first mode and the second mode.

A measurement device is provided with: a measurement unit including a first mode that measures an electrical resistance of a recording medium used in an image forming apparatus in a first predetermined range of electrical resistance values and a second mode that measures the electrical resistance in a second range of electrical resistance values different from the first range, the second range and the first range being set such that with respect to the electrical resistance of multiple brands of recording media, a number of brands belonging to the second range is greater than a number of brands belonging to the first range; and a control unit that controls the measurement unit to prioritize execution of the second mode over the first mode.

A measurement device includes: a resistance measurement unit that measures an electrical resistance of a measurement target; a first measurement unit, including a detector that detects information indicating a first physical property other than the electrical resistance of the measurement target, that measures the first physical property from a detection result from the detector; a second measurement unit, including a detector that detects information indicating a second physical property other than the electrical resistance and the first physical property of the measurement target, that measures the second physical property from a detection result from the detector, in which a length of time from a start of driving the detector until a start of actual measurement is longer in the second measurement unit than in the first measurement unit; and a control unit that performs first control causing the first measurement unit to execute a measurement operation of measuring the first physical property in parallel with a measurement operation by the resistance measurement unit, and performs second control causing the second measurement unit to execute a measurement operation of measuring the second physical property in parallel with the measurement operation by the resistance measurement unit and also causing the second measurement unit to start the driving of the detector in the second measurement unit before the start of the driving of the detector in the first measurement unit.

A recording medium determination device includes a light emitter, a light detector, and a hardware processor. The light emitter emits inspection light to a recording medium. The light detector detects incident light including at least one of diffuse reflected light of the inspection light emitted to the recording medium and fluorescent light excited by the inspection light in the recording medium. The hardware processor makes a determination depending on a property of the recording medium based on a detection result of first incident light of the incident light in accordance with first inspection light of the inspection light and second incident light of the incident light in accordance with second inspection light of the inspection light obtained by the light detector. The second inspection light has an intensity whose peak wavelength is shorter than the peak wavelength of the first inspection light.

A sheet discharge device includes: at least one processor; a conveyance unit configured to convey a sheet along a conveyance path; a discharge unit to which the sheet is discharged; a storage unit that is provided in a middle of the conveyance path and temporarily stores the sheet; an alignment unit provided in the discharge unit and configured to align the sheet in a width direction intersecting a convey direction of the sheet, in which the processor is configured to change a method of aligning the sheets by the alignment unit between a case where storage control for storing the sheets in the storage unit is performed and a case where the storage control is not performed.

A physical property detecting device, includes: an insertion part that includes an insertion port through which a sheet is inserted and removed; a first physical property detector that detects a first physical property of the sheet in a non-nipping state; and a second physical property detector that nips the sheet and detects a second physical property of the sheet in a nipping state, wherein the first physical property detector and the second physical property detector are disposed at different positions in an insertion and removal direction of the sheet.

In a case where feeding of a subsequent sheet by a feed roller is started after the trailing edge of a preceding sheet is detected by a post-registration sensor, a control unit of a sheet feeder controls the feed roller to rotate at a first feeding speed, and in a case where the leading edge of the subsequent sheet has passed through a nip position between the feed roller and a separation roller, the control unit controls the feed roller to rotate at a second feeding speed.

In an image forming apparatus, a detecting unit is configured to detect a characteristic value indicating a characteristic of a recording material fed from a sheet feeding unit. A determination unit is configured to determine a type of the recording material, based on the detected characteristic value and a determination rule for determining a type of a recording material. A control unit is configured to control an image forming condition for performing image formation onto the recording material in accordance with the determined type of the recording material. A collection unit is configured to collect an operation history of the image forming apparatus. An adjustment unit is configured to adjust the determination rule used by the determination unit based on the collected operation history.

An image forming device includes an image carrier, a transfer member, a fixing device, a conveyance member, and a controller. The transfer member forms a transfer nip that transfers an image carried on the image carrier to a recording medium. The fixing device fixes the image on the recording medium. The conveyance member is located downstream of the transfer member in a conveyance direction of the recording medium and feeds the recording medium to the fixing device. The controller variably controls position of the conveyance member.

A digital printing system (10) includes a flexible substrate (44), an optical assembly (200, 301) and a processor (20). The flexible substrate (44) has a periodic pattern, and is configured to be moved and to receive ink droplets in a printing process that forms an image thereon. The optical assembly (200, 301) is configured to illuminate the flexible substrate (44) with light (215, 315), to detect the light (215, 315) from the flexible substrate (44), and to derive from the detected light (215, 315) a signal indicative of the periodic pattern. The processor (20) is configured to receive the signal and to monitor or control the digital printing system (10) based on the periodic pattern as indicated by the signal.