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.

Provided are an image forming system and a method for detecting glossiness capable of accurately detecting glossiness in various media having different conditions.

The image forming system includes a sensor unit including a light source that irradiates a medium being conveyed with light and a gloss sensor that receives light emitted from the light source and specularly reflected on the medium and detects a diffusion distribution of light in the medium, and a detection condition setting unit that identifies a type of the medium being conveyed and sets a light amount of the light source and/or exposure time of the gloss sensor at the time of glossiness detection in accordance with the type of the medium. The image forming system further includes a glossiness detector that detects glossiness of the medium from a diffusion distribution of light detected by the gloss sensor under the detection condition set by the detection condition setting unit.

An image forming system including: a reading unit configured to read, through a transparent member, an image on a first sheet conveyed by a conveyance unit; an opposed member provided opposite to the reading unit with respect to the transparent member, the first sheet passing through a gap between the opposed member and the transparent member; and at least one processor configured to control, based on the image read by the reading unit, a geometric characteristic of an image to be formed on a second sheet by an image forming portion, and control a changing unit to change the size of the gap to a first size when the thickness of the first sheet is a first thickness, and to a second size larger than the first size when the thickness of the first sheet is a second thickness larger than the first thickness.

An information processing apparatus includes a processor configured to: obtain characteristic values including smoothness and basis weight of a recording medium; and identify the type of the recording medium on the basis of the smoothness and the basis weight.

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.

An image forming system including: a reading unit configured to read, through a transparent member, an image on a first sheet conveyed by a conveyance unit; an opposed member provided opposite to the reading unit with respect to the transparent member, the first sheet passing through a gap between the opposed member and the transparent member; and at least one processor configured to control, based on the image read by the reading unit, a geometric characteristic of an image to be formed on a second sheet by an image forming portion, and control a changing unit to change the size of the gap to a first size when the thickness of the first sheet is a first thickness, and to a second size larger than the first size when the thickness of the first sheet is a second thickness larger than the first thickness.

An image forming device includes: a conveyance path that conveys a printing medium; an image former that is arranged in a first place in the middle of the conveyance path, forms an image on one surface of the printing medium, and fixes the formed image by heating; a cooler that is arranged in a second place downstream in a conveyance direction from the first place in the middle of the conveyance path, and cools the printing medium by blowing air for cooling to the printing medium; and a reader that is arranged in a third place downstream in the conveyance direction from the second place in the middle of the conveyance path, and reads the image formed on the printing medium, wherein between the first place and the second place of the conveyance path, one or a plurality of guide members is provided, and a guide member is not provided.

An image reading apparatus connectable to an image forming apparatus includes a feeding roller pair configured to nip and feed a sheet discharged from the image forming apparatus, a contact image sensor configured to read an image on a first surface of the sheet fed by the feeding roller pair, a light-transmissive plate provided opposed to the contact image sensor and having a light-transmission property, a first roller opposing the light-transmissive plate with a gap therebetween on a side opposite from the contact image sensor with respect to the light-transmissive plat, and a second roller positioned upstream of the first roller with respect to a sheet feeding direction and opposing the light-transmissive plate with a gap therebetween on the same side as the first roller.